E&E 2016 Abstracts of accepted papersE 2016 Abstracts of accepted papers 1. ... Alexandre1, Laurent,...

E&E Congress 2016 | 6th Eurasphalt & Eurobitume Congress | 1-3 June 2016 | Prague, Czech Republic

E&E 2016

Abstracts of accepted papers

1. Warm mixtures

New foamed/modified bitumen using phosphogypsum waste

ID: 18

Cuadri, Antonio Abad1, Navarro, Francisco Javier

1, García-Morales, Moisés

1, Partal, Pedro

1

1 Department of Chemical Engineering, University of Huelva, Huelva, Spain

Topic: 1. Warm mixtures

This paper describes a new alternative way to produce foamed bitumen, by using

phosphogypsum wastes (PG), which is also able to enhance the mechanical behavior of the

resulting binder. PG waste is generated worldwide from the production of phosphoric acid

and deposited in stacks, causing environmental problems. The results obtained point out that

the addition of 10 wt.% PG to a 35/50 paving grade bitumen, when activated with a small

amount of strong acid, results in a foamed bitumen with enhanced the rheological properties,

especially at high in-service temperatures, after foam collapses. This is mainly attributed to

the existence of chemical reactions involving phosphorus compounds contained in the PG,

forming new chemical links with some bitumen molecules. Another positive aspect of this

technology is that this method produces more stable bitumen foam if compared to the

traditional processes, i.e. through direct injection of water. Thus, the combined effect of

temperature and the activation agent (sulphuric acid) gives rise to dehydration of the

structural water contained in PG yielding foamed bitumen.


Assessment of the performances of foamed asphalt mix containing RA

ID: 56

Somé, Ciryle1, Pavoine, Alexandre

1, Laurent, De Marco

1, Gaudefroy, Vincent

2, Andrieux,

Laura1, Gérard, Di Stasio

1, Roberto, Andrade

1

1 Laboratoire EcoMatériaux (LEM), CEREMA, Sourdun, France

2 IFSTTAR, Nantes, France


A series of laboratory tests have been performed to evaluate the rutting depths and the water

sensitivities of French BBSG 3, 0/10 asphalt mixtures (EN 13108-1 (2007)) containing

reclaimed asphalt pavement (RA). Two soft binders and one reference paving grade bitumen

have been used to produce the mixes: a soft 50/70 grade bitumen (Nyfoam 60) a very soft

160/220 bitumen (Nyfoam 190) and a reference 35/50 bitumen. The mixes have been

manufactured in warm (WMA) and hot mix asphalt (HMA) conditions thanks to a new

laboratory foaming plant. The foaming parameters such as the half-life time (t1/2) and the

expansion ratio (ER) have been optimized based on a parametric study. The influence of RA

content has been evaluated using Wheel track (EN 12697-22) and water sensitivity (EN

12697-12) tests. It was found that the increase of the RA content decrease the rutting depth.

For the high RA content, the water sensitivities comply with the EN 13108-1 (2007)

requirements.


Warm mix asphalt: an insight on durability and eco-friendliness

ID: 81

Melero Corell, Jorge1

1 Asphalt Pavements, Bundesanstalt für Straßenwesen, Bergisch Gladbach, Germany


Warm mix asphalt techniques have been around for a couple of years since the first field tests

started across different European countries. Temperature reduction has potential to reduce

pollutant emissions while achieving similar or equal performance to traditional hot mix, on

the one hand, and health-damaging gases, on the other. Several software suites have been

published to address the environmental impact of a road or a given pavement. Among these

are, for example, ECORCE (France), asPECT (United Kingdom) and CEREAL (European).

Each one differs in the way they encompass all project stages and the pollutants they evaluate.

Furthermore, they allow editing their database. Environmental benefits of warm mix were

assessed using them. Furthermore, the quality of the built-in data was also assessed

comparing the supplied data with real data of German asphalt plants. In order to assess the

field performance of warm mix, road condition data from two German test sites (A1 and A7

motorways) were evaluated. These sections have recently reached an age from which long-

term conclusions can be inferred. This study aims to compare the environmental and

durability benefits of new asphalt technologies using real data and a direct comparison of the

asPECT software’s results.


Effect of RAP temperature on asphalt mix performances (hot and warm)

ID: 84

Carbonneau, Xavier1, Legal, Yves

1, Quigniot, Sebastien

1, Desroches, Myriam

2

1 Asphalt mixes department, Campus for Science and Techniques COLAS, magny les

hameaux cedex, France

2 Chemistry department, Campus for Science and Technique, Magny les Hameaux cedex,

France


Warm mixes are still the main issue in road construction. Environmental and economics

stresses lead necessary to a combination of these technologies with recycling. These new

ways to produce asphalt mixes face several problems, resulting from their specific

composition and way of production. Mix designs studies in laboratories are not well adapted

to make these mixes in a way close to what is produced in plants. Questions arise about how

to prepare RAP and to produce mixes in lab when foam is used. When mix design is only

based on laboratory studies, this can slow down the acceptance of these technologies. To

promote these techniques, Colas has implemented an important test program, and on site

measurements on new plants. A mobile laboratory has been installed and the main existing

industrial processes of production, with additives and foam, using RAP warmed or not, have

been fully evaluated. Workability, water resistance, but also mechanical performances used in

a fundamental approach necessary for pavement design have been completely assessed. Usual

mix design of the same mixes has been conducted in the laboratory with materials sampled at

the plant, allowing to be sure that no bias could come from the components. Wearing and base

courses with 40% RAP content has been studied. The question of the blending of the binders

has been evaluated through a detailed analysis of all the binders, pure, extracted from RAP,

and extracted from the mixes. Both performance tests and chemical composition of the

binders have been investigated, in order to draw some relationships with the mix

performances. We especially focused on the state of aging of the binders. The main

characteristic of this experimental trial was that it covers all the existing productions

capabilities on the same site. The effect of the process, production of a hot or warm mix,

using cold or heated RAP, was fully covered, giving us a necessary better understanding of

the effect of the process, leading to more relevant criteria to obtain optimized warm mixes

with RAP. These will be an important reference to increase the development of warm mixes

with RAP


Permanent deformation characteristics of warm mix asphalt

ID: 87

Oner, Julide1, Topal, Ali

1, Sengoz, Burak

1, Aghazadeh Dokandari, Peyman

1

1 Civil Engineering, Dokuz Eylul University, Engineering Faculty, IZMIR, Turkey


Warm Mix Asphalt (WMA) is a technology that allows lowering the production and paving

temperature compared to Hot Mix Asphalt (HMA). The reduction of temperature enables

various benefits over asphalt mixtures such as decreasing greenhouse gas emissions, lowering

energy consumption, fuel cost saving, improved workability and easy compaction. Besides,

WMA technology gives an option to use Recycled Asphalt Pavement (RAP) that provides a

very economic method and eco-friendly pavements. The objective of this study was to

evaluate the utilization of organic and chemical WMA additives with different percentages of

RAP. Following the determination of optimum RAP contents corresponding to each WMA

additive Hamburg Wheel Tracking Test is performed to obtain the permanent deformation

characteristics of mixtures containing optimum RAP contents.


Successful demonstration of lower temperature asphalt on the UK strategic

road network

ID: 131

Wayman, Matthew1, Nicholls, Cliff

1, Carswell, Ian

1, Artamendi, Ignacio

2, Phillips, Paul

2, 3,

Khojinian, Arash4, James, Donna

4, Simms, Malcolm

3, Southwell, Chris

5

1 TRL Limited, Wokingham, United Kingdom

2 Aggregate Industries, Coalville, United Kingdom

3 Mineral Products Association, London, United Kingdom

4 Highways England, Guildford, United Kingdom

5 Eurobitume UK, Harrogate, United Kingdom


Lower temperature asphalts (LTAs) have been identified as a way of reducing both the energy

required to produce and lay asphalt materials and the nuisance of fumes for workers. The use

of LTAs has not yet reached its full potential in the United Kingdom. To encourage uptake in

appropriate applications and inform the national specifications, a project was undertaken to

demonstrate use of a LTA on the strategic road network. The project was realised as a result

of successful collaboration between the national road authority, industry and a research

organisation. A site with sections of LTA surface and binder course mixtures produced using

an ‘injection foaming’ technology was laid and monitored for initial properties. Sections of

conventional hot mix materials were also laid and monitored to enable direct comparison.

Visual inspection, temperature measurement and thermographic imaging were undertaken at

regular intervals throughout construction. Physical properties of the materials used were

established through laboratory testing of samples taken at site and the carbon footprint of

construction was evaluated. Overall, the demonstration proved that effective application of an

LTA technology could be achieved but also yielded some important practical messages for

the future application of LTAs.


Asphalt recycling and foam bitumen – a combined approach

ID: 137

Bieder, Andrea1, Hofer, Thomas

1, Demarmels, Anton

1

1 Research & Development, Ammann Construction Equipment, Langenthal, Switzerland


To save resources and reduce the energy consumption during asphalt mix production there are

three main approaches: addition of reclaimed asphalt (RAP), lower production temperatures,

and reduced moisture content in raw materials. Whereas a high moisture content only

influences, thus increases the energy consumption and emissions in the plant, RAP addition

and lower production temperatures have a direct impact on asphalt mix properties. The main

goal of this study is the production of high quality asphalt mix. Experience has proven that

high ratios of reclaimed asphalt can be incorporated into hot mix asphalt at equal quality.

Furthermore using foam bitumen to produce warm mix allows mixing and compaction at

reduced temperatures with comparable properties to hot mix. Combining asphalt recycling

and foam bitumen is a step forward to an efficient and sustainable use of resources. The

feasibility of producing high quality warm mix asphalt with foam bitumen and various high

RAP percentages was demonstrated in field trials. In several asphalt mixing plants mixes were

produced, paved and compacted at reduced temperatures. Asphalt production and laying was

attended and analyzed. Additionally, for direct comparison construction sites with

conventional hot mix were observed. Mechanical mix properties equal to hot mix asphalt

were found independent of the RAP content and production temperature.


Benefits of F-T wax based warm asphalt mixes for short-term binder aging

and pavement durability

ID: 148

Simnofske, Diana1, Mollenhauer, Konrad

1, Butz, Thorsten

2, Oelkers, Carsten

2

1 Institute of Transportation, University of Kassel, Kassel, Germany

2 Sasol Performance Chemicals, Wax Division, Hamburg, Germany


Wax based warm mix additives are increasingly applied to enable asphalt mixing and paving

at lower temperatures or to improve the workability and compactability of hot-mix asphalt at

conventional temperatures. The effects of these wax additives on the rheological behaviour

and mechanical properties of bitumen and asphalt were already extensively investigated.

Effects on the chemical properties of bitumen, such as aging, are largely unknown. For

evaluating the effects of F-T wax, 50/70 bitumen was modified with F-T wax and analysed

after short term aging (RTFOT). RTFOT at 163°C simulated the asphalt mixing and paving at

conventional temperature. Warm mix conditions were simulated by RTFOT at 143°C in order

to consider the lower mixing temperatures in the plant. The aging of the binders was

characterised by measuring rheological properties (DSR, penetration, softening point),

chemical analysis (IR spectroscopy; SARA chromatography) and analysis of the colloidal

components (asphaltenes fractionation). The results show that the chemical composition is

only determined by the bitumen characteristics. F-T wax modification significantly influences

the mechanical properties after ageing. Compared to the unmodified binder, wax modification

results in decreased effects of ageing on the shear properties in the complete service

temperature range. The warm mix aging simulation indicated the significantly reduced aging

and the resulting potential for increased pavement durability by applying wax additives.


New compactability parameter for comparing warm mix additives

ID: 153

Smith, Mark 1, James, Alan

2

1 Asphalt Applications, Akzo Nobel Surface Chemistry AB, Stenungsund, Sweden

2 Asphalt Applications, AkzoNobel Surface Chemistry LLC, Brewster, NY, United States


There are several methods for assessing compaction of asphalt mixtures offering some

insights into compactability and density during and after compaction. This information can be

used in pavement design calculations, but is usually too imprecise to assess performance of

Warm Mix Asphalt (WMA) additive chemistry. The NCHRP issued a “mix design practices”

report 691 which details a gyration ratio method where a mixture’s compactability is

calculated. This formed the basis of the study where the functionality of WMA additives

could be measured via an added “performance ratio”. The research supported and steered

development of WMA additive chemistry for the paving industry giving reliable and

reproducible results where the degree of performance of WMA additives could be observed.

The research method used 30kg lab batches of asphalt material manufactured using a small

scale pug-mill with twin shaft mixers and a Hobart planetary mixer and Marshall Hammer,

Cooper gyratory and Infratest roller compactors. The results from each compaction method

were compared and then the asphalt gyration and performance ratios were calculated together

with mechanical performance measured by Indirect Tensile Strength ratio (ITSR) and Wheel-

Track permanent deformation. The research was conducted using the appropriate EU and

AASHTO standards together with additional laboratory techniques we have developed giving

more reliability in the results. The conclusions facilitated the development of test methods

which have been used for research into new Warm Mix Asphalt additives.


Instrumentation and in-situ evaluation of warm mix asphalt test sections

ID: 163

Bueche, Nicolas1, Dumont, André-Gilles

1, Angst, Christian

2

1 Traffic Facilities Laboratory, Ecole Polytechnique Fédérale de Lausanne, Lausanne,

Switzerland

2 IMP Bautest AG, Oberbuchsiten, Switzerland


Warm Mix Asphalt (WMA) is widely considered as a potential alternative to conventional

Hot Mix Asphalt (HMA) that enables reducing the environmental impacts of the road

construction phase. Thus, an ambitious project dedicated to WMA has been launched in 2011

by the Federal Roads Office (FEDRO). The PLANET (PotentieL et ANalyse des Enrobés

Tièdes) project contains a specific work package dedicated to the construction, monitoring

and evaluation of four different WMA test sections in addition to a reference HMA. The

tested techniques involved chemical additives, the uses of zeolite as well as bitumen foaming.

RAP addition has also been considered. Several in-situ testing have been conducted in order

to compare the WMA techniques. To do this, the test sections have been instrumented using

strain gauges and temperature sensors and two measurements campaigns performed with a

control truck load. The pavement bearing capacity has also been analyzed through falling

weight deflectometer (FWD) measurements. Besides, an extensive laboratory testing

campaign has been conducted on the asphalt mixtures and cores taken after different periods

of time in order to assess a potential evolution of some mechanical properties or

characteristics. The obtained results permitted to highlight the differences between WMA

techniques as well as providing good practice guideline for future applications.


Comparing evaluation of compacting capability of foamed bitumen asphalt

mixes

ID: 176

Puchard, Zoltan1, Gorgenyi, Agnes

1

1 Technology Department, Colas Hungaria Zrt., Budapest, Hungary


COLAS Group in Hungary considers the use of low temperature asphalts as a high priority

innovation task. Since 2008 we have been dealing with LT asphalts. First we made LT

asphalts with additives later we changed for foamed bitumen. Between 2012 and 2014,

COLAS Group equipped its asphalt mixers with units from different manufacturers, capable

of producing foamed bitumen, at four COLAS Group mixing plants in Hungary. In addition,

the central laboratory of COLAS Hungária Zrt. also has a foaming device for laboratory use.

Testing the compacting capability properties of foamed bituminous mixtures is deemed to be

of prime importance for us. The compacting of asphalt mixtures containing different sorts

(normal and modified) of bitumen manufactured using laboratory-produced foamed and

normal bitumen has been tested on test specimens produced using gyrator and Marshall

compactor. At the mixing plant, the compacting capability of asphalt mixtures manufactured

using the four different foaming kits has been determined for test specimens produced using

Marshall compactor, and the results have been compared reference asphalt test specimens.

Each asphalt mixture manufactured using four different foaming kits has been built into a test

section. At these sections, the compacting capability of foamed bitumen asphalt mixtures have

also be studied, and compared with reference asphalt mixes. The presentation give a summary

of the evaluation of results from laboratory tests and the experiences regarding asphalt

productions and test sections produced with four different foaming kits.


Environmental and mechanical evaluation of warm mix asphalts in laboratory

and on site

ID: 184

Baptiste, Vincent1, Jullien, Agnès

2, Moglia, Olivier

1, Oro Urrea, Leire

3, Oster, Mélanie

4,

Pouget, Simon4, Paillac, Jean-Philippe

3, Lapalu, Laurence

3, Dauvergne, Michel

2

1 Total Marketing Services, Nanterre, France

2 IFSTTAR, Bouguenais, France

3 Total Marketing Services, Solaize, France

4 Eiffage Travaux Publics, Corbas, France


Warm asphalt mixes made with ready to use binders or with other types of technology like

bitumen foam are commonly used in France and elsewhere. In order to develop knowledge on

the different technologies, an experimental trial has been organized in September 2013 in

partnership between TOTAL Marketing Services, Eiffage TP and Ifsttar. The purpose of the

test was to carry out environmental assessment of the warm mixes comparatively to

traditional hot mixes. 4 sections have been realized (hot mix asphalt, warm mix asphalt with

respectively ready to use binder, foam, and combination of foam and ready to use binder).

The asphalt plant had been equipped in order to record energy consumption and to monitor

the chimney emissions. On average the different warm mix technologies lead to savings on

energy consumption and on greenhouse effect gases. Extensive asphalt quality data like for

example voids contents and macrotexture have also been recorded during the trial. Stiffness

tests have also been carried out on cores. Performances of warm mixes are equivalent to the

ones obtained with hot mix. A follow-up of the test is planned.


Tribological and wettability study of non foaming warm mix asphalt additives

at mixing and compaction temperatures

ID: 186

Geisler, Flavien1, Kapsa, Philippe

1, Lapalu, Laurence

2

1 Laboratoire de Tribologie et Dynamique des Systèmes, CNRS - Ecole Centrale de Lyon,

ECULLY, France

2 Centre de Recherche, TOTAL MARKETING AND SERVICES, SOLAIZE, France


Foaming process and additivation of bitumens are now commonly used technologies to

produce Warm Mix Asphalt (WMA). However, the mechanisms of such technologies are still

not well understood. In this study, we focus on non-foaming WMA additives. A literature

review shows that this kind of additives have only a slight impact on the viscosity of bitumens

and allocates them lubricant and adhesion promoting properties. So they are thought to act at

the surface of aggregates. In order to better understand their mechanisms during the mixing,

lay down and compaction steps, both tribological and wetting experiments were conducted at

high temperatures. On the one hand, friction experiments were conducted on a linear

reciprocating tribometer in order to investigate the effect of additives on friction process

between aggregates. In this test, a ball slides on a flat mineral aggregate immersed in hot

bitumen. Both hydrodynamic and boundary lubrication conditions were investigated. On the

other hand, the effects of WMA additives on the surface tension of neat bitumen were

determined and the spreading of a drop of bitumen on the mineral aggregate was also

investigated. Promising results indicate that organic and chemical additives don’t get the same

friction behaviour in boundary lubrication regime. Their contribution to surface tension is

although discussed.


Evaluation methods of chemical additives used in warm and recycled asphalts

Mixtures

ID: 188

Gonzalez-Leon, Juan1, Achard, Françoise

1, Falletti, Olivier

1

1 Centre de Recherche de Rhones Alpes, ARKEMA, Pierre Benite, France


After several years of field trials and millions of tons of asphalt mix produced using warm

mix asphalt (WMA) technologies, the chemical additive technology has been identified as the

most robust, economical and simple to use. It has already been reported in multiple occasions

that the mechanical properties of asphalt mixtures using surfactant-based additives are similar

or better than those obtained in regular hot mix asphalts. There are, however, some aspects of

their implementation that are still studied, mainly due to the lack of simple laboratory

evaluation methods. Here, two important issues related to the use of chemical additives in

asphalts mixtures are discussed. The first is related to the environmental concerns that the use

of such additives can generate. A relatively simple analytical method is shown to be capable

of identifying changes in the gaseous emissions due to the addition of chemical additives. The

method is based on the chromatographic analysis of the emissions produced by hot asphalt

binder. Through this method, differences in emissions between bitumens, their usage

temperatures and the presence of additives are shown. The second is about the assessment of

the workability of asphalt mixtures in the laboratory. Evaluating the workability is important

for the selection of the proper additive for WMA and also for hot mix asphalt that needs

compaction aids due to its high stiffness or because of its particular handling requirements.

This is a subject that has been studied for many years and, although there have been important

advancements; there is still no standardized method for evaluating the workability of asphalt

mixtures in the laboratory. In this work, a simple method based on the use of the gyratory

compactor is shown to be able to help in the evaluation of the asphalt mixture workability.

The method is capable of demonstrating the effects on the mix workability of different

bitumen grades, different temperatures and surfactant additives, as those used in the

production of WMA.


Long term properties assessment of HMA and WMA with RAP through the

apparent molecular weight distribution variation of the bitumen

ID: 190

Perez-Martinez, Miguel1, Marsac, Paul

1, Themeli, Andrea

1, Chailleux, Emmanuel

1, Lopes,

Manuela2, Gabet, Thomas

1, Hammoum, Ferhat

1

1 Department of Transport Infrastructure Materials, IFSTTAR, Bouguenais, France

2 Polytechnic School University of São Paulo, University of São Paulo, São Paulo, Brazil


The δ-method previously developed in IFSTTAR, is employed to determine the long term

properties of asphalt mixes with reclaimed asphalt. This δ-method allows the calculation of

apparent molecular weight distribution from rheological measurements. Its potential benefits

as a tool for better understanding the key points of bituminous mixes recycling process is

assessed. The study is carried out on twelve mixtures including two different types of warm

mix asphalt techniques (surfactant and foamed bitumen) combined with the addition of high

rates of reclaimed asphalt pavement. Samples are submitted to an oxidative aging process

based on the protocol proposed by the RILEM Technical Committee-ATB TG5 consisting in

two separate aging phases, a short term stage (corresponding to transport and spreading) and a

long term aging equivalent to service life. The changes observed on the apparent molecular

weight distribution with ageing and/or when reclaimed asphalt is added show that the δ-

method could help to characterize structural ageing according to the different mixtures

processes and its evolution. This may allow a better assessment for the long term

performances of bituminous mixes depending on the manufacturing process.


Mechanical properties and quality-control of warm asphalt

ID: 231

Angst, Christian Dr.1, Bueche, Nicolas Dr.

2


2 Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland


The aim of the research project PLANET is to provide road experts with technical know-how

for the production of bituminous mixtures and paving with low energy and environmental

impacts. In this paper the objectives are to assess the methods of control that are usually

applied to hot mixes and to make an in-depth study of the mechanical behaviour of the

different warm-asphalt technologies in comparison with a similar hot mixed asphalt. Five test

fields with 4 different warm-asphalt technologies and one with hot mix-asphalt have been

realised. The mixing and laying procedures has been fully documented and the methods of

quality control that are usually used were applied. For this purpose a protocol of preparing the

sample in the laboratory has been established. A huge amount of samples and cores were

tested by different test methods, such as interlayer bonding, rutting test, uni- and triaxial

cyclic compression test, water sensitivity, fatigue, modulus of elasticity, and indirect tensile

test at different temperatures. To assess the time-depended increase of the interlayer bonding

a laboratory test-program has been run. The results will be presented and discussed.


Development and performance of new additives for warm mix asphalt

technologies

ID: 267

Sağlık, Ahmet1, Demir, Birol

1, Oral, Hakan

1, Ozturk, Tuğba

1, Güngör, Ahmet Gürkan

2

1 Research and Development Department, General Directorate of Turkish Highways, Ankara,

Turkey

2 Inspection Board, General Directorate of Turkish Highways, Ankara, Turkey


Warm mix asphalt (WMA) is a growing sustainable pavement technology reducing the

production and paving temperature of asphalt mixture by 20-40 oC without compromising the

performance. The main advantages of WMA are reduced fuel consumption, increased hauling

distance, extended paving season, better compaction, reduced emissions and binder oxidation.

In this study, it was attempted to develop a new zeolitic and paraffinic WMA additives. Warm

mix asphalt mixtures with commercial and newly produced additives were subjected to the

rutting, fatigue, water sensitivity (ITSR) and workability tests in laboratory. The two of the

additives performing best in laboratory were used in WMA production in real field

application. It was seen that all additives gave small amount of reduction in ITSR

performance but similar performance in rutting and fatigue in laboratory. However actual

field application showed that the additives provide better compatibility and same as or better

performance than hot mix in all respects. This paper evaluates laboratory and field

performance of commercial and newly developed WMA additives.


Performance of asphalt mixes with high recycling rates for wearing layers

ID: 296

Blasl, Anita1, Kraft, Juliane

1, Lo Presti, Davide

2, Di Mino, Gaetano

3, Wellner, Frohmut

1

1 Institute for Pavement and Urban Engineering, Technical University of Dresden, Dresden,

Germany

2 Faculty of Engineering, University of Nottingham, Nottingham, United Kingdom

3 Department of Civil, Environmental, Aerospace, Materials Engineering, University of

Palermo, Palermo, Italy


The corresponding paper presents selected results of a research on the feasibility of going

toward 100% recycling of asphalt pavements into surface courses through an increasing

percentage of RA within the mixes. The research is carried out within a two-year CEDR

Transnational Road Research project, AllBack2Pave, led by the Technische Universitaet

Dresden (Germany), together with the University of Nottingham (UK) and the University of

Palermo (Italy), and finalised in January 2016. The main objectives of the project are - to

establish, through laboratory tests on binders and asphalt mixes, whether the use of high rates

of RA is feasible in developing mixes with high level of durability, and - to develop a

"AllBack2Pave end-user manual” on how to best produce cost-effective and high-quality

asphalt mixes with high RA content followed by a sustainability assessment of the practice of

using asphalt surface mixes with high recycling rates based on chosen European case studies

to identify the most cost-effective solutions, together with their environmental impact over the

whole lifecycle of selected road pavements. The paper focus on selected results of laboratory

tests conducted for different types of representative asphalt surface mixes with different

amounts of reclaimed asphalt as well as for the bitumen extracted from the investigated

asphalt mixes. In detail, the thermal cracking resistance of the used bitumen will be analysed

and critical temperatures will be given. Regarding the asphalt mixes, the stiffness behaviour

and the rutting resistance of all materials will be discussed.


Use of plastomeric additives to improve mechanical performance of warm mix

asphalt

ID: 319

Lecomte, Michael1, Hacker, Scott

2, Teymourpour, Pouya

3, Bahia, Hussain

3

1 Specialty Additives, Honeywell Belgium NV, Leuven, Belgium

2 Specialty Additives, Honeywell International, Morristown, United States

3 Department of Civil and Environmental Engineering, University of Wisconsin, Madison,

United States


A number of asphalt modifiers are known to improve the engineering characteristics of

asphalt mixtures. However, asphalt mixtures produced with Polymer Modified Bitumen

(PMB) are sometimes difficult to handle, and in many cases need higher mixing and

compaction temperatures whereas the asphalt industry strives to reduce these temperatures in

order to decrease energy consumption and harmful emissions of typically used Hot Mix

Asphalts (HMA). This paper investigates if plastomeric materials (or a combination of

elastomeric and plastomeric materials) can lead to better mechanical properties while

reducing the processing temperatures. It shows that some low molecular weight poly-olefins

having low viscosities above their melting point can act as processing aids and change the

initial/inherent aggregate structure of the mixture (i.e., aggregates’ packing) during

compaction. This effect has been obtained with or without combination of elastomeric

modifiers. The improved aggregate packing observed using image analysis tool (“iPas2”) has

a significant impact on performance-related properties like rutting resistance and complex

modulus. Moreover, when the oxidized poly-olefins are used in the PMB, the polymer

modified mixture appeared to be less sensitive to moisture damage as measured in water

boiling tests and in modified Lottman test (ITSR).


Laboratory assessment of new technical solutions for mastic asphalt with

reduced mixing temperature

ID: 350

Mondschein, Petr1, Miláčková, Kristýna

1, Soukupová, Lucie

1, Valentin, Jan

1, Bureš, Petr

2,

Kašpar, Jiří2

1 Department of Road Structures, Czech Technical University in Prague, Faculty of Civil

Engineering, Praha, Czech Republic

2 Eurovia Services s.r.o., Prague, Czech Republic


Mastic asphalt is still an important type of asphalt mix used in several European countries

especially for applications on bridge pavement structures as a waterproofing layer or even

binder/wearing course. Similarly it is used for tram tracks to fix the structure in the existing

road. Last but not least it is used for trafficked areas with heavy loading or very low traffic

speed (parking garages, storage areas etc.). Since REACH was introduced to European

legislation and bitumen including its applications was registered there is an ongoing effort to

reach mastic asphalt variants where the processing temperature would be at maximum 200°C.

Within the research activities of Centre for Effective and Sustainable Traffic Infrastructure,

which is the only R&D centre of competence financed in this area by the Czech government a

subtask was done with focus on different possibilities to design and assess mastic asphalt with

reduced processing temperature. Besides the known waxes which are used since many years,

some new alternatives were tested. Additionally also a surfactant and additives based on sugar

cane extracts were included as well as some less known wax based additives. Firstly bitumen

(20/30) treated by these additives was analysed by standard empirical tests and mainly

performance based test focusing on dynamic viscosity, MSCR test and frequency sweep test

on DSR. For some additives different ratios were applied to discuss the impact of such

additive. In the second stage mastic asphalt MA11 (eventually MA8) was produced in the

laboratory with assessment of workability given in Czech technical standards and the stiffness

test according to the EN standard. Especially because of the bridge deck applications also the

rip-off test was done. The mixes were produced by different temperatures to analyse the effect

of the used additives in the binder.


Impact of selected WMA additives on normal PMB used for a standardized

SMA

ID: 351

Valentin, Jan1, Valentová, Tereza

1, Soukupová, Lucie

1, Bureš, Petr

2, Kašpar, Jiří

2



2 Eurovia Services, s.r.o., Prague, Czech Republic


WMA techniques are well known for many years, even if still not increasingly popular in

Europe. In the Czech Republic so far these techniques – mainly different types of wax based

additives and surfactants – were used for asphalt concrete and usually in combination with a

normal pen grade (70/100 or 50/70). As part of an ongoing research the focus was laid on

SMA mixes which are as in any other country used mainly as a top wearing course for

pavements with highest loadings and life-time expectations. Even if it is still allowed to use

normal distilled bitumen, the best effect is achieved if PMBs are applied. For this reason a

typical mix design for SMA11 mix was selected and more than 15 different binders have been

used divided in three groups – two where effect of different WMA additives was analysed on

PMB 25/55-55 of two selected origins and last group containing a more modified binder (not

for WMA) and a 50/70 binder modified by PPA. As WMA additives different waxes have

been used, selected surfactants and a nano-based additive. Firstly all bituminous binders were

analysed by empirical tests, dynamic viscosity, MSCR and frequency sweep test. Then the

mixes were prepared with a temperature reduced by 20-25°C in comparison to reference mix,

For all mixes voids content, stiffness, ITSR, rutting and crack propagation was analysed and

will be summarized in the paper.


Laboratory Evaluation of rutting performance of warm mix asphalt with

Nano base and Fischer-Tropsch wax additive

ID: 404

Khadem, Mahmood 1, Ziari, Hassan

1, Moniri, Ali

1

1 Department of civil engineering, Iran University of Science and Technology ( IUST),

Tehran, Iran


Mixing temperature of asphalt concrete can be lower using new technology called warm mix

asphalt (WMA). WMA technology has lots of advantages such as needing less energy,

emitting less gaseous pollutants and having less construction cost. However, this technology

has some unfavorable features such as high moisture susceptibility. Different kinds of WMA

additive improve resistance of mixtures against moisture damage substantially. On the other

hand, some other features of WMA mixtures produced using WMA additive like resistance to

permanent deformation need more investigations. In this study the Marshall and rutting

performance of Nano base mixtures were investigated and compared to Fischer tropsch wax

mixtures as control mix. The results indicated that the mixtures containing Nano base additive

had less marshal stability and rutting resistance than Fischer tropsch wax mixtures.


Laboratory evaluation of half warm recycling with bio-based additive

ID: 414

Porot, Laurent1, Eduard, Pieter

1

1 Arizona Chemical, Almere, Netherlands


It is now widely recognized that Reclaimed Asphalt (RA) is a valuable source of material for

asphalt mixes. RA provides a sustainable solution with both economic and environmental

benefits. This value can currently be realized in cold recycling as with using emulsions, or in

hot in plant reuse. In addition to these methods, an alternative may be to use a half-warm

process, typically at a C. Because RA contains aged binder that is hardertemperature below

120 than standard bituminous binder, it requires an elevated temperature in order to

“mobilise” the binder. At lower mixing temperatures, such as ambient temperature or that

used in half-warm mix, the RA is usually considered to be “black-rock” aggregate-like in

character, providing no cohesion/strength in the asphalt mixture. Although processing at these

lower temperatures produces lower performance mixes that do not attain specification levels

equal to HMA, there are certain economic advantages that can be realized. A laboratory study

has been conducted to evaluate the effect of a highly effective bio-based additive in

combination with 100 % RA. The main challenge was determining how the binder from the

RA can be mobilized at ambient temperature and above, and whether some cohesion and

strength can be imparted. The study utilized simple asphalt testing such as a gyratory

compaction and Indirect Tensile Strength measurements, and the results indicate that 100 %

RA treated with a limited amount of additive can attain characteristics similar at least to those

produced by cold mixing asphalt or half-warm mix asphalt (HWMA). Furthermore, in this

case, no curing time was required. This new technology could find applications in hot in-place

recycling, C,C to 180 where the temperature of the milled road can vary from 80 C, or even

withcold in-plant recycling with a temperature above 60 pretreatment of RA on the

stockpile.


Master curves of crumb rubber modified binders containing Montan waxes as

warm mix asphalt additives

ID: 415

Rodríguez-Alloza, Ana María1, Gallego, Juan

2

1 Department of Civil Engineering: Construction, Infrastructure and Transport, Technical

University of Madrid (UPM), Madrid, Spain

2 Department of Civil Engineering: Transport, Technical University of Madrid (UPM),

Madrid, Spain


Energy consumption and the corresponding greenhouse gas (GHG) emissions can be reduced

with technology recently developed in the field of road pavement materials: warm mix asphalt

(WMA). This technology is being incorporated to improve workability and, consequently,

production and compaction temperatures of asphalt mixtures can be lowered without

significantly affecting their mechanical properties. However, since this technology is

relatively new, the influence of WMA additives on the properties of crumb rubber modified

(CRM) binders has not yet been investigated in depth and clearly identified. The main

objective of this study is to investigate the effect of different types and quantities of WMA

additives on the high and intermediate temperature properties of a 20%CRM binder. For this

purpose, binder´s properties are determined using a dynamic shear rheometer (DSR) which

allows elastic, viscoelastic and viscous properties of bitumen to be defined over a wide range

of temperatures and frequencies. The results of this study indicate that there are significant

improvements produced by the additives concerning the mechanical behaviour and the

elasticity for the whole temperature range; the complex modulus (stiffness) is increased at the

high temperatures avoiding permanent deformation and the phase angle curve is shifted on

lower values over a wide range of frequencies. However, the increased content of additives

slightly shifted the complex modulus master curves in high frequency regions, increasing the

stiffness at low temperatures.


Stiffness, Creep Properties and XRD Analysis of a New Fast-Curing Cold Mix

Asphalt for Use in Highway Pavement

ID: 423

Al Nageim, Hassan1, Al-Busaltan, Shakir

2

1 School of Built Environment, Liverpool John Moores University, Liverpool, United

Kingdom

2 Civil Engineering Department, University of Kerbala, Kerbala, Iraq


The paper reports the stiffness and creep properties and XRD analysis of a new cold mix

asphalts developed for use in highway pavement surface layers. The high voidage, low

stiffness modulus and long curing time which normally spans approximately from two months

to 24 months has restricted road engineers to allow these materials for use in road

experiencing low traffics. To remove the above restriction, the main filler in the traditional

Cold Bituminous Emulsified Mixtures CBEM’s is replaced with treated biomass waste fly ash

materials. The new filler has increased the stiffness and creep properties of the new CBEM’s

and hence provide new CBEM’s product possessing the following advantages compared with

traditional Hot Mix asphalt (HMA); 1. reduced energy of production, 2. reduced emission of

pollutants, 3. reduced pavement total construction costs As well as providing a use for what

would otherwise become a hazardous land fill waste products. The fly ash used in this

research project is available in more than 250,000 tonne annually in the UK and more than

this quantity in Europe, USA, and worldwide. This new products will contribute in an

outstanding percentage of reducing CO2 emission when the new products finds its way to

replace HMA prepared and constructed at 120C0 to 170C0. A treated biomass fly ash, which

is waste or by-product material, was incorporated in the cold bituminous emulsion mixtures

with five percentages of replacement to mineral traditional filer ranging from 0 to 5.5% of

aggregate weight in the mixture. The results have shown outstanding comparative

improvement in the stiffness and creep properties of the new cold mixtures compared with

traditional cold mix asphalt. The reason for achieving these results was explained in this paper

by using XRD analysis of the fine mineral-emulsified mortar used in this study.


2. Recycling

Recycling at the highest level - today solutions for the standards of tomorrow

ID: 28

Port, Ralf1, Schriek, Hans-Joachim

1, Herges, Horst

2, Herges, Horst

2

1 Sales Departement, Benninghoven GmbH & Co. KG, Mülheim an der Mosel, Germany

2 Technical Director, Benninghoven GmbH & Co. KG, Mülheim an der Mosel, Germany

Topic: 2. Recycling

The Asphalt Industry constantly searches for new solutions in order to optimise processes

within the Asphalt Plant. A major subject is the increase of RAP content in all recipes.

Recycling Parallel Drum Systems work in various sizes and at various power levels. This

technique has been established by different producers over the decades. However, all kinds of

concepts in heating up RAP material in the parallel flow system has its limits. The physical

properties of the parallel flow drum system came with some negative characteristics such as

high exhaust gas temperatures to reach the RAP material product temperature and high

emission levels, which lead us into a new development with our long term partner BAM

(Bavarian Asphalt Plant Works) to find a different way forward for this technology. In the

mid 1980´ the technique of indirectly heating the RAP utilising a hot gas generator was

introduced but not perfected, unlike the new system. For Benninghoven´s Development

Technical Team the biggest challenge was to configure the fan arrangements for recirculation

and exhaust conditions based on theoretical values. Based on the calculated theoretical values

the system was technically configured. Additional to this some specific specialties were taken

into consideration. A real challenge for the Development Team was how to handle the fine

particles in the exhaust gas. A simple and ingenious solution was found. The dirt gases first

reach a generously sized expansion chamber where the air speed is reduced. The particles then

fall into a collection hopper and they are transferred by a screw conveyor into the hot

recycling buffer silo. The development teams were astonished that the estimated values were

exceeded. During the testing phase the system was closely monitored, emission tests were

taken, samples were analysed, recipes created were modified accordingly, and processes were

optimised with the result that the plant performed to 100% of the specification. The computer

monitor screen shows a filter exhaust gas temperature of 90°C and a recycling product

temperature of 172°C. The C Total value had been constantly recorded to be below 50 mg,

therefore these values are well below the applicable norm of Germany’s “TA-Air”.


Pyrolytic product used as an alternative binder rejuvenator

ID: 29

Avsenik, Lidija1, Tušar, Marjan

1

1 National Institute of Chemistry, Ljubljana, Slovenia

Topic: 2. Recycling

Binder rejuvenators are additives which purpose is to return aged bitumen its original

properties. That means we can use a higher proportion of reclaimed asphalt pavement (RAP)

in asphalt mixture when we add rejuvenator. Till now for rejuvenators were used different

materials e.g. flux oil, tertiary amines, emulsions, soft bitumen, and combination of different

compounds. In our research binder rejuvenator produced from scrap tires was tested. For

producing so called alternative binder rejuvenator (BR) the pyrolysis process will be used.

Prior to the production, pyrolysis process was properly modified in order to get the BR with

adequate properties. By changing the time and temperature of the pyrolysis process we

obtained different pyrolytic products. All of them and their blends with reference bitumen

were investigated using standard tests for bituminous mixtures. Results of the tests showed

that some of the pyrolytic products could be used as a binder rejuvenator. Test showed that

milder terms of pyrolysis are more appropriate for rejuvenator production. Further tests on

bitumen, aged bitumen and asphalt mixtures will be done to get more information about this

new products.


The use of rubber granulate in bitumen and asphalt

ID: 48

Rudi, Elena1, Cetinkaya, Reha

1, Schmidt, Hans

1

1 Basalt-Actien-Gesellschaft, Linz am Rhein, Germany

Topic: 2. Recycling

Crumb rubber can be used as a high quality additive for bitumen and thus provides another

way of bitumen modification. Consequently, crumb rubber modified bitumen (CRMB) can be

an alternative to polymer modified bitumen (PMB). Rubber granulates are made of old truck

tires. The recycling of the tires is meant to achieve a CO2 reduction [Manke et. al, 2013].

Furthermore, the sustainability will be improved by preserving the natural resources. Of

course, the protection of the environment is not the only reason for the use of CRMB in

asphalt. The concrete advantage of rubber modified bitumen is that its rheological properties

are improved as well as the mechanical properties of asphalt. In the present examination

report the bitumen products as well as the final asphalt are examined. The comparison

between two products of crumb rubber modified bitumen with one product of polymer

modified bitumen shows that rubber modified bitumen is absolutely equivalent to polymer

modified bitumen and thus indeed suitable for binder modification as well. Cold temperature

tests reveal a similar performance of CRMB in comparison to PMB. Testing final asphalt

samples, those samples produced with PMB have a comparable low-temperature behaviour as

samples produced with CRMB. Generally it has to be pointed out that the influence on the

bitumen varies depending on the producer.


Performance control of bituminous mixture with a high RAP content

ID: 50

Delfosse, Frédéric1, Drouadaine, Ivan

1, Faucon- Dumont, Stéphane

1, Largeaud, Sabine

1,

Decamps, Jacques Antoine1

1 EUROVIA, Mérignac, France

Topic: 2. Recycling

To conserve natural resources and reduce greenhouse gas emissions, the use of Reclaimed

Asphalt Pavement (RAP) becomes essential. In order to allow an increase of the RAP content

in our bituminous mixtures without affecting either sustainability or the mechanical

performance, a lot of research is conducted by the road building companies. A key point lies

in a thorough knowledge of the bituminous mix (physico-chemical properties, homogeneity)

obtained by blending new and aged bitumen (i.e. recovered bitumen coming from the

RAP).These parameters will be affected by the mode of incorporation of RAP and therefore

the type of mixing plant. At the same time, new techniques are being developed to reduce the

temperature at which asphalt concretes are produced, from 30 to 50°C. This decrease in

temperature directly affects the viscosity of the bitumen and therefore also the kinetic of

remobilization (bitumen blending). The simultaneous goal of increasing the rate of RAP and

reducing production temperature leads to technical limitations undefined to date. Through

some examples, this paper presents a methodology to describe the remobilization of different

bitumen, to predict the mechanical properties of recycled asphalt, to adjust the asphalt

concrete parameters more precisely for future production and asphalt design. The first part

presents a new procedure to describe the blending between the aged (RAP) and the new

bitumen. It allows a progressive extraction of the bitumen from asphalt with a specific solvent

followed by physico-chemical analysis of these samples (leachate). In the second part, a

rheological model of modulus prediction of the asphalt concrete specifically developed from

the rheological properties of the bitumen and volume distribution of the constituents of the

asphalt concrete will be presented.


Effect and efficiency of rejuvenators on aged asphalt binder – German

experiences

ID: 51

Radenberg, Martin1, Boetcher, Sabine

1, Sedaghat, Natasha

2

1 Lehrstuhl für Verkehrswegebau, Ruhr-Universität Bochum, Bochum, Germany

2 BP Europe SE, Bochum, Germany

Topic: 2. Recycling

Due to aging process of bitumen and its corresponding increase in viscosity, the stiffness of

asphalt pavement increases during its lifetime. Therefore, high addition rates of Reclaimed

Asphalt Pavement (RAP) in asphalt mixtures may negatively influence a mixture’s quality.

As a consequence, asphalt recycling is predominantly used in the asphalt’s base layers

(asphalt and unbound). Yet, with regards to the current importance of sustainability and

protection of resources, it is becoming increasingly desirable to raise the addition rates of

RAP in top layers. Rejuvenating agents can assist in this process by decreasing the aged

bitumen’s viscosity and restoring its original properties. Chemically, the relation between

solid asphaltenes and liquid maltenes in the bitumen shifts towards a higher maltene content.

The german research project “Use of Rejuvenators for Asphalt Recycling” concerns itself

with the efficiency of rejuvenators as well as with the effect such additives have on aged

bitumen properties. To this end, all rejuvenators available worldwide (21) have been acquired

and then mixed with extracted bitumen of asphalts of differing ages. Furthermore, the

rheological and physical properties of the mixtures were investigated before and after

laboratory aging. Finally, selected mixes of the rejuvenators and the extracted bitumen were

subjected to performance tests. This project’s goal is to provide a technology for the use of

rejuvenators in Germany by defining the properties of rejuvenators that are necessary to

enable the efficient recycling of existing asphalt pavements.


Bitumen fatigue performance evaluation - with or without RAP - a real

challenge

ID: 55

van Rooijen, Ronald1, Planque, Luc

2, Wegmann, Marcel

1, Di Benedetto, Hervé

3, Mangiafico,

Salvatore 3, Sauzeat, Cedric

3, Olard, François

4, Pouget, Simon

4

1 GFT Bitumen, BP Europa SE, Gelsenkirchen, Germany

2 Services Bitumes, BP France, Cergy Pontoise, France

3 ENTPE, Université de Lyon, Vaulx-en-Velin, France

4 Direction R&D, Eiffage Infrastructures, Corbas, France

Topic: 2. Recycling

Bitumen plays an important role in asphalt pavement fatigue. For normal paving grade

bitumen fatigue performance generally improves with increasing penetration. However, this

general rule does not hold for special binders like high stiffness binders, polymer modified

bitumen and Multigrade bitumen. An estimation of the fatigue performance becomes even

more difficult when part of the bitumen comes from reclaimed asphalt pavements (RAP).

Evaluation of bitumen fatigue performance and the effect of RAP bitumen on bitumen fatigue

performance are the main topics of this paper. The fatigue performance of 10 binders was

investigated with a DSR time sweep test at constant strain amplitude. The binders were tested

with and without bitumen that was recovered from RAP. Addition of up to 40 % RAP

bitumen has various but little effect on the fatigue performance of standard paving grade

bitumen but for the better performing bitumen products the shear strain amplitudes

corresponding to a fatigue life of 10^6 cycles decreases significantly. When all 10 bitumen

products - with known significant differences in fatigue performance - are considered, a good

correlation with asphalt fatigue performance as measured with the 2-point bending test is

observed. The DSR time sweep test method is not a practical tool to asses fatigue

performance of bitumen as it takes a long time to complete the tests and reproducibility is

poor. A number of binders have been tested according to the recently developed Linear

Amplitude Sweep (LAS) test to investigate if this test has potential as practical test method to

evaluate fatigue performance of bitumen. Some of the results presented in this paper are from

a research project that has been carried out in collaboration between ENTPE in Lyon,

EIFFAGE and BP. This research addressed the influence of asphalt mix design parameters on

the mechanical response of bituminous mixtures produced with RAP. Scope and some of the

main findings and conclusions of this work have already been presented at different

international congresses and in a number of scientific publications.


The development of 100% RAP asphalt mixture with the use of innovative

rejuvenator

ID: 93

Hagos, Eyassu1, Shirazi, Morteza

2, Wall, Alex van de

3

1 KWS-InfraLinQ, Hoogblokland, Netherlands

2 Latexfalt BV, Koudekerk aan den Rijn, Netherlands

3 KWS-InfraLinQ, Vianen, Netherlands

Topic: 2. Recycling

The use of up to 50% Recycled Asphalt Pavement (RAP) in asphalt mixtures is a standard

practice in the Netherlands. There is a high demand to increase the percentage of RAP in

asphalt mixtures because of the economic and environmental benefits. Currently the

maximum possible use of RAP without a rejuvenator is about 70%. One of the factors

limiting the use of high percentages of RAP is the hardening of bitumen in the RAP because

of aging. In this study the use of 100% RAP with the addition of a rejuvenator was

successfully implemented. The rejuvenator was developed to restore the original

characteristics of the bitumen and its effectiveness has improved the characteristics of 100%

RAP mixture. Performance indicators such as stiffness en fatigue characteristics were

researched. Comparable mixture performance with a reference asphalt mixture has been

achieved. As a follow up of this research a test section of 100% RAP has been laid to verify

the test results. The use of high percentage RAP seems promising not only in the underlying

asphalt layers but also in top layers.


Cold recycling process using renewable resources: contribution of rheological

and chromatographic methods for rejuvenating mechanism and duration

assessment

ID: 106

Durand, Graziella1, Lorserie, Aurélie

1, Gueit, Carole

1

1 Road Chemistry Service, COLAS Campus for Sciences and Techniques, Magny-les-

Hameaux, France

Topic: 2. Recycling

Recycling end-of-life road products can be performed in various ways, involving a

combination of sustainable techniques. A first level in sustainability is reached by the use of a

bitumen emulsion, which enables processing at moderate temperatures. This technique is

already commonly used, according to specific guidelines. Further improvement is achieved if

the emulsion contains a rejuvenating agent manufactured from renewable resources. In this

context, the key issue in laboratory study is to find a proper way to highlight the rejuvenating

effect and to follow its evolution. Suitable test methods, described in this paper, have been

identified and used for this purpose. The general principle is to compare binder characteristics

after extraction from RAP, and from mixes obtained after recycling process and in situ-aging ;

several aging steps are considered. The rejuvenating effect is supposed to end when the

characteristics of binder from mix after recycling are back to those of the RAP binder.

Dynamic Shear Rheometer (DSR) enables to determine the binder stiffness modulus as a

function of temperature: thus, thermal sensitivity is monitored, along with binder hardness. In

the first weeks after recycling process, the binder tends to soften, due to the progressive

rejuvenating effect. Afterwards, the binder hardens slowly throughout months. After 1 year in

situ, a rejuvenating effect is still observed. Chromatographic methods such as gaseous

chromatography (simulated distillation) enable to monitor the chemical evolution of the

rejuvenating agent itself, within the blend with RAP binder and rejuvenation bitumen. After 1

year aging in situ, the rejuvenating agent is no longer detected, through its effect can still be

seen though rheological properties. Considering results obtained by both kinds of techniques,

a hypothesis can be proposed, in order to explain the action mechanism of the rejuvenating

agent. This latter is most likely to have delayed binder hardening. Hence, the efficiency of

rejuvenating process has been improved by lengthening its effect, in comparison with

performances attributed to a pure bitumen emulsion.


Life cycle evaluation for reusing Reclaimed Asphalt with a bio-rejuvenating

agent

ID: 115

Porot, Laurent1, Di Nolfo, Maria

1, Polastro, Enrico

2, Tulcinsky, Sonia

2

1 Roads and Construction, Arizona Chemical BV., Almere, Netherlands

2 Arthur D. Little, Brussels, Belgium

Topic: 2. Recycling

Reusing Reclaimed Asphalt (RA) in new pavement imparts both economic value and

environmental benefits to the industry. Environmental impact is an important parameter to be

addressed in Environmental Product Declarations, which may be requested in the near future

in Europe. As part of these environmental impact determinations, carbon footprint

calculations are a key element for estimating climate change drivers. This paper discusses the

life cycle evaluation of an asphalt mixture with a high RA percentage. Percentages of RA

above 30–40 % require specific technologies to overcome technical challenges, and in this

study, the use of a bio-based rejuvenating agent was taken into account. The use of such a

rejuvenating agent ensures that the end performance of the asphalt mixture is equal to or

better than a standard asphalt mixture without RA. Calculations were based on a specific

study for one metric ton of Hot Mix Asphalt (HMA) produced with 70% RA. Although the

contribution of the bio-rejuvenating agent to the carbon footprint is limited, the results clearly

highlight the benefits of reusing high volumes of RA in HMA by reducing the overall carbon

footprint for production of the mix. Key words: Reclaimed Asphalt, recycling, asphalt, bio-

rejuvenator, carbon footprint, Life Cycle Assessment, sustainable development


Comparison between laboratory results for cold recycled bound materials and

DBM 50 used in airfield pavements

ID: 120

Lacalle Jiménez, Helena Isabel1, 2

, Thom, Nicholas2, Edwards, J. Paul

1

1 Pavement Design and Asset Management, Civil and Infrastructure, AECOM, Nottingham,

United Kingdom

2 NTEC, University of Nottingham, Nottingham, United Kingdom

Topic: 2. Recycling

Cold recycled materials are widely used in UK road construction, but their use in airfield

pavements is less common. The UK has adopted the concept of sustainable development and

cold recycling of asphalt into foamed or emulsion bitumen bound materials minimizes the

waste generation and reduces the consumption of finite resources. In addition, this technique

has the added benefit of readily incorporating recycled asphalt which contains tar, making

cold recycling an attractive option for the rehabilitation of airfield pavements. The challenge

is that there is no specific pavement design guidance for these materials and the current

practice is to conservatively equate these materials to an assumed performance of a hot

asphalt mixture. The objective of this paper is to verify if this practice is accurate when

analyzing these materials’ performance, especially through laboratory testing. The results

presented in this paper show that the pavement design could be optimized and that a design

guide based on cold recycled materials is needed to gain confidence and extend the use of

cold recycled bitumen bound materials in airfields. This conclusion forms the basis for the

SUP&R ITN project ESR1: “Pavement design for cold recycled materials”.


Towards production of 100% recycled asphalt

ID: 125

Zaumanis, Martins1, Mallick, Rajib B.

2, Frank, Robert

3

1 Research Management and Development Department, Latvian State Roads, Riga, Latvia

2 Civil and Environmental Engineering, Worcester Polytechnic Institute, Worcester, MA,

United States

3 RAP Technologies, Linwood, NJ, United States

Topic: 2. Recycling

Re-use of old asphalt materials for production of new pavements is increasing every year.

Because of reduced costs this is encouraged by public agencies. Re-use also reduces

environmental footprint through lower emissions and avoiding extraction and processing of

natural resources. But recycled contents are limited by current production technologies and

mix design principles. To further increase recycling rate while ensuring quality pavement, a

move towards fundamental, performance related specifications is necessary. This article

presents a study aimed at developing procedures that enable up to 100% recycling of asphalt

pavement in hot-mix asphalt. A mix design approach is presented based on performance

related test methods both for binder and mixture. Validation of this method is based on

laboratory performance of 100% reclaimed asphalt modified by six different rejuvenators.

Rejuvenator dose optimization procedure is presented and the results demonstrate that the

approach can be used to restore the desired performance grade (PG) of aged RAP bitumen.

100% recycled asphalt mixtures, modified with the same six rejuvenators, were tested for

rutting and low temperature cracking and the results indicated that optimal design can provide

performance equivalent to virgin mixture. Rutting requirements were satisfied for all six

rejuvenated mixtures and five of them reduced the critical cracking temperature compared to

the RAP mixture based on creep compliance and tensile strength results.


Two case studies with high levels of RA enabled by a rejuvenating agent

ID: 132

Gomes, Vitor1, Di Nolfo, Maria

1, Vlachos, Panagiotis

1, Bocci, Maurizio

2


2 Ingegneria Civile, Edile e Architettura - Sezione Infrastrutture - Area Strade, Universitá

Politecnica delle Marche, Ancona, Italy

Topic: 2. Recycling

Sustainability is a recurring theme for the paving industry due to economic and environmental

benefits. Global focus is increasing on the proper reuse of valuable recyclable materials,

including Reclaimed Asphalt (RA). Reusing RA in new pavement provides economic

advantages by reducing natural resource requirements. However, care must be taken to

maintain the same level of performance for the end product. For the asphalt industry, there are

two barriers to incorporating more RA. One involves overcoming the poor quality of the aged

binder in the RA. The other relates to specifications that do not allow high percentages of RA

even where the final performance is proven. In Italy, national specifications do not currently

allow more than 25% RA due to anticipated poor performance. Nevertheless, the national

industry is highly interested regarding RA in new asphalt mixtures. To enable incorporation

of high amounts of RA while maintaining final asphalt mix performance, a bio-based

rejuvenating agent was designed to restore the properties of aged RA binder. This innovative

product was validated in the laboratory by testing RA binder and RA-containing asphalt

mixes. Afterwards, asphalt mixes with 40% and 50% RA were scaled up in two trials on

national highways, using mixes from two different plants. Samples were collected from these

trials, allowing evaluation of the performance of the produced mixes, and enabling

comparison with earlier laboratory validations. Based on these results, this product enables

the use of higher amounts of RA in new asphalt mixes while maintaining performance levels.

Overcoming the barrier of poor performance would allow future changes in specification

limits. Key words: Reclaimed Asphalt, RA, RAP, recycling, asphalt, bio-rejuvenator,

rejuvenation, Environmental, Reusing


Development of RAP binder characterisation tests for use within viscosity

grade binder specification framework

ID: 150

Denneman, Erik1, Lee, Jeffrey

1, Petho, Laszlo

1, Choi, Young

1, Dias, Melissa

1

1 Pavement Technology, ARRB Group, Brisbane, Australia

Topic: 2. Recycling

Reclaimed asphalt pavement (RAP) is increasingly being re-used in new asphalt products.

The properties of the binder in RAP will affect the behaviour of the asphalt material,

especially for products containing a considerable proportion of RAP. This paper presents the

results of a study aimed at developing an improved methodology of characterising RAP

binder blends within a viscosity grade binder specification framework. The methodology

comprises measurement of a complex viscosity parameter for the RAP binder using the

dynamic shear rheometer (DSR). The parameter was selected to be comparable to the

capillary tube viscosity, a test typically used in viscosity grade specifications for bitumen in

Australia. The parameter can be used in the design of blends of RAP binder and virgin binder

and/or rejuvenator to a specified viscosity value. The study included two experimental phases:

the first phase was aimed at developing the DSR-based methodology for characterisation of

the RAP binder; and in the second phase, performance-related tests on laboratory prepared

asphalt mixes containing different percentages of RAP were performed to validate the binder

characterisation methodology. The experimental work showed that the DSR can be used for

viscosity measurement as an alternative to both the sliding plate micro-viscometer and the

capillary viscosity test. The experiments on asphalt mixes containing various percentages of

RAP showed the influence of RAP content on flexural modulus, fatigue and rut resistance of

the material. The performance-related testing of asphalt mixes further confirmed that the RAP

binder characterisation methodology developed as part of this study can be used to design

binder blends containing RAP, virgin binder and rejuvenator, in such a way that the overall

performance of a high RAP content mix is similar to that of a mix containing only virgin

materials.


Tolerances for inhomogeneity of pavement structure for in-situ cold recycling

ID: 151

Mollenhauer, Konrad1, Simnofske, Diana

1

1 Engineering and Maintenance of Road Infrastructure, University of Kassel, Kassel,

Germany

Topic: 2. Recycling

Cold recycling technique is a road construction method for producing a new base layer from

existing road material. For in-situ cold recycling, a recycler mills the existing road structure in

a depth up to 30 cm by mixing these materials with bituminous emulsion or foamed bitumen

and/or hydraulic binder (e.g. cement). The composition of the mix granulates results from the

structure of the recovered pavement and may contain different proportions of reclaimed

asphalt, reclaimed cement concrete and reclaimed unbound material. The mix design of the

new cold-recycling material is optimised for the site-specific mix granulate composition.

Though, pavement structures may show inhomogeneities due to partly conducted road

maintenance, road widening or former excavation works. In this study it is evaluated, in what

extend inhomogeneities in pavement structure will influence the mechanical properties of

cold recycling materials. Therefore, cold recycling mixtures are produced with constant

binder content by varying the mix granulate composition (reclaimed asphalt, reclaimed

cement concrete and reclaimed unbound material) to evaluate the sensitivity of the material

performance on differing pavement structures. As a bias, it is evaluated if the binder of the

reclaimed asphalt materials affects the properties of the new cold recycled material. In total

eight different cold recycling mixes were produced in laboratory by varying the composition

of the mix granulate material. All mixtures were produced with the same grading, a constant

residual virgin bitumen content of 4% and cement content of 2%. After static compaction,

indirect tensile strength after 7 and 28 days of conditioning, water susceptibility and CBR

properties were tested. Limits of pavement inhomogeneity could be evaluated which may be

tolerated during cold recycling mix application. Further the test results indicate a significant

effect of old RA bitumen on the performance of the cold recycled material.


MURE National Project: FTIR spectroscopy study to assess ageing of asphalt

mixtures

ID: 154

Dony, Anne1, Ziyani, Layella

1, Drouadaine, Ivan

2, Pouget, Simon

3, Faucon-Dumont,

Stéphane2, Simard, Delphine

3, Mouillet, Virginie

4, Poirier, Jean Eric

5, Gabet, Thomas

6,

Boulange, Laurence7, Nicolai, Aurélia

8, Gueit, Carole

5

1 Université Paris Est, IRC, ESTP, Cachan, France

2 CRM, EUROVIA, Mérignac, France

3 CER, EIFFAGE Travaux Publics, Corbas, France

4 DT Méditerranée, CEREMA, Aix-en-Provence, France

5 CST, COLAS, Magny Les Hameaux, France

6 IFSTTAR, MAST, LUNAM University, Nantes, France

7 EIFFAGE Travaux Publics, Neuilly sur Marne, France

8 Direction Technique & Développement, MALET, Portet-sur-Garonne, France

Topic: 2. Recycling

The French national project MURE, a collaborative research and development programme,

started in March 2014. Two main issues are addressed: coupling of recycling and warm-mix

asphalt technique and multi-recycling of bituminous mixtures. It gathers the national road

federation, academic laboratories, road contractors and project contracting officials. The

objective of the first working group (WG1) of MURE is to validate an accelerated ageing

process for bituminous mixtures as well as on site than in laboratory. To achieve this goal, it

is first necessary to characterize the ageing using a reliable and reproducible method valid for

laboratory and plant-made mixtures. Many studies from the literature showed the efficiency

of FTIR spectroscopy for ageing identification. In particular, carbonyl and sulfoxide groups

found in binders are appropriate ageing markers. Meanwhile, no common FTIR protocol does

exist at present. The first step of the experimental work performed by the WG1 was to

compare seven FTIR methods, differing from sample preparation and approaches for

calculating spectroscopic indexes. One given bitumen was aged eight times successively by

RTFOT method (75 min – 163 °C). Two IR spectrum acquisition modes were tested:

attenuated total reflectance (ATR) and transmission (spreading of bitumen on an IR

transparent plate and bitumen dissolution in a solvent). The second step of the study was to

verify the repeatability of FTIR tests on neat and aged bitumen according to sample

preparation and calculation methods. The results allow confirming the relevance of FTIR

spectroscopy for qualifying bitumen ageing. A single methodology and a common tool for

harmonizing the calculation of indexes are proposed. The whole procedure can be used to

follow the ageing properties on site at short and long times.


The water resistance recycled base with the foamed bitumen in the aspect of

hydraulic road binder

ID: 166

Marek, Iwański1, Przemysław, Buczyński

1, Grzegorz, Mazurek

1

1 Transportation Engineering, Faculty of Civil Engineering and Architecture, Kielce

University of Technology, Kielce, Poland

Topic: 2. Recycling

This paper describes preliminary research results of recycled base properties which was

performed in cold deep recycling technology with the foamed bitumen and different kind of

the hydraulic road binder in the aspect of water resistance. The design of the recycled base

layer simulated a deep cold recycling process with materials derived from crushed bituminous

pavement layers ("in-situ" technology). To manufacture the foam bitumen was used a road

bitumen of penetration grade 50/70. As a binders were used road binders. They were

manufactured in the laboratory through the mixing of the three basic components in the

proportions set according to the plan of the experiment. For the purpose of determine the

influence of such hydraulic road binder on the water resistance of the recycled base the

following test were carried out: void contents Vm, absorbability nw, indirect tensile strength

ITSDRY at 25OC, tensile strength ratio TSR (water resistance). Additionally the evaluation

of the increase in indirect tensile modulus (IT-CY) was made. On the basis of received test

results it was observed the different impact of tested hydraulic road binders on properties of

the recycled base with the foamed bitumen. With regard to the design of experiment plan it

was possible to determine the recommended road binder composition that allows to obtain

requisite the water resistance of the recycled base with foamed bitumen.


Microstructural analysis of asphalt mixtures containing recycled asphalt

materials using digital image processing

ID: 195

Cannone Falchetto, Augusto1, Moon, Ki Hoon

2, Wistuba, Michael P.

1

1 Department of Civil Engineering, Technische Universität Braunschweig, Braunschweig,

Germany

2 Material R&D Division, Samsung Corporation, Seoul, South Korea

Topic: 2. Recycling

The use of recycled materials in pavement construction has seen, over the years, a significant

increase closely associated to substantial economic benefits and to the demand of

environmentally friendly constructions materials which limit the intensive exploitation of

natural resources. Over the past decades, the use of different types of recyclable materials

such as Reclaimed Asphalt Pavement (RAP) has been considered. However, most research

efforts investigating the effect of adding recycled asphalt materials in asphalt paving mixtures

were focused on experimental testing and performance evaluation, while the effect on asphalt

mixtures microstructure has only recently seen increased attention. In this paper, the effect of

adding RAP on the microstructural properties of asphalt mixtures is investigated using digital

image processing (DIP) of digitalized images acquired by scanning Bending Beam Rheometer

(BBR) specimens made of asphalt mixture. Detailed information on the internal

microstructure is obtained from Red Green and Blue (RGB) images of small BBR beams and

based on three-phase material analysis (aggregate, asphalt mastic and air voids). The

numerical estimations of the spatial correlation functions and of the corresponding

autocorrelation length (ACL) are then performed to quantitatively determine the impact of the

recycled material on spatial distribution of the three mixture phases. The microstructural

distributions of aggregates, asphalt mastic, and air voids were not significantly affected by the

addition of RAP up to 40%. However, an increase in Auto Correlation Length (ACL) was

found for RAP mixtures in comparison with conventional mixtures. The proposed DIP

analysis method has the potential of being used as a forensic quality control tool to verify if

the mixing process affects the microstructural distribution of the asphalt mixture constituents

potentially resulting in poor mechanical performance.


Laboratory experience with the application of monotonic triaxial test on the

cold recycled asphalt mixes

ID: 220

Čížková, Zuzana1, Šedina, Jakub

1, Valentin, Jan

1, Engels, Michael

2



2 Wirtgen GmbH, WIndhagen, Germany

Topic: 2. Recycling

Besides cracking, cold recycled asphalt mixtures are deteriorated due to permanent

deformation as well. For evaluating these rutting properties in order to allow a suitable

pavement design based on the significant mechanical properties of cold recycled asphalt

materials, monotonic triaxial tests can be applied. Specimens with a diameter of 150 mm and

a height of 300 mm are subjected to monotonically increased vertical compression stress until

specimen failure whereas a radial confining stress is maintained constant. By conducting

triaxial tests with varied confining stress, the shear strength for various stress conditions will

be evaluated. This paper is focused on the description of the test device, the test methodology

as well as the assessment of test results. Further the specimen preparation procedures are

discussed as identified as significantly relevant for simulating the field performance of cold

recycled asphalt mixtures. Finally the effect of variation in binder content (bituminous binder

– emulsion and foamed bitumen) and hydraulic binder are discussed.


Double Coating of Full Depth Reclamation Materials

ID: 227

Gandi, Apparao1, BenSalem, Fahd

1, Bressi, Sara

2, Carter, Alan

1, Bueche, Nicolas

3

1 Ecole de technologie superieure, Montreal, Canada

2 Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland

3 Nibuxs, Lausanne, Switzerland

Topic: 2. Recycling

Full Depth Reclamation (FDR) and Cold In-Place Recycling (CIR) are popular rehabilitation

techniques for flexible pavement. Both techniques can be done with the addition of asphalt

emulsion or foamed bitumen as a stabilizer. In most cases, those two techniques to add

bitumen are considered equivalent, even if the way they give cohesion to the mix is different.

A research project was undertaken to verify the possibility of using both asphalt emulsion and

foamed bitumen on FDR materials to have better mechanical characteristics since it’s

believed that asphalt emulsion gives a good coating, and foamed asphalt does not coat as well

but serves as a binding agent. FDR mixes were prepared in the laboratory with and without

asphalt emulsion and foamed bitumen. Different addition processes were tested in order to

find the optimum mix design procedure. Moisture susceptibility tests (Marshall tests and

indirect tension tests) and complex modulus tests were performed on the different mixes, and

it was shown that the use of both binders can give you a mix with better performance. This

paper presents the mix design, the test program and the results of this study.


Performance evaluation and behavior of microsurfacing with recycled

materials

ID: 234

Garfa, Arbia1, 2

, Dony, Anne2, Carter, Alan

1

1 école de technologie supérieure, montréal, Canada

2 Université Paris Est, ESTP-IRC, cachan, France

Topic: 2. Recycling

Road networks play a vital role in the development of country’s economy. It is necessary to

develop new technologies to improve the performance and safety of the roads. Added to that,

it is necessary to enhance the evolution of the roadways over time in terms of maintaining its

surface while respecting the challenges of sustainable development. Microsurfacing is one of

the techniques used to satisfy these challenges. However, there is very little information on

the evolution and behavior of the product on short and long term, and there is no information

on the use of recycled materials in the latter. In this context, this study aims to study and

improve the performance of mixtures of microsurfacing with recycled materials. After the

development of an adapted accelerated aging method on Microsurfacing, materials were

prepared in lab with reclaimed asphalt pavement (RAP) and with recycled asphalt shingles. It

was shown that it’s possible to prepare microsurfacing with 100% RAP while respecting all

International Slurry Surfacing Association (ISSA) standards. The results have shown that the

filler’s characteristics have a big impact on the rutting resistance of those mixes. Procedures

were developed during this project to measure the water sensitivity of the mixtures and their

behavior over time.


Evaluation of Slag as aggregates in Asphalt Mixtures

ID: 238

Viman, Leif1, Ahmed, Abubeker W.

1, Said, Safwat

1, Lind, Lotta

2

1 VTI, Linköping, Sweden

2 Lindskan AB, Ånge, Sweden

Topic: 2. Recycling

During the last decade, the Swedish Transport Administration together with contractors, Steel

industry in Sweden and the Swedish National Road and Transport Research Institute have

built test road sections with Steel slag in various locations in Sweden. Steel slag has well-

known good adhesion, durability, wear resistance and noise reducing properties. This project

pointed out the importance for steel slag producers to produce a slag quality that fulfils the

requirements as road material, where also particle emission is an important issue. There are

over 10 producers of steel slag in Sweden. There are several goals for using steel slag in

asphalt mixes; mainly longer technical lifetime caused by good wear resistance against

studded tyres, good stability performance in binder and base course, and good durability

performance, the latter being especially important in porous asphalt, where it also

potentiallygives some noise-reducing effects. In addition, the environmental aspects in terms

of particle emission, were an important issue for this project. So far, test sections show good

performance according to road surface measurements. Laboratory test according to European

standards for aggregate and several road simulator test for wear resistance and particle

emission have been performed during the last five years by means of the unique road

simulator at VTI. An important part of the project is to increase the knowledge for the steel

slag producers to develop a material that fulfils the requirements for road material in as many

aspects as possible, both technical and environmental issues. The results are so far promising

and expectations are met.


New concept of sustainable road structure with RAP binder course using bio-

agent

ID: 260

Kowalski, Karol J.1, Król, Jan B.

1, Radziszewski, Piotr

1, Piłat, Jerzy

1, Sarnowski, Michał

1

1 The Faculty of Civil Engineering, Warsaw University of Technology, Warsaw, Poland

Topic: 2. Recycling

Growing demand on paving materials requires application of recycling materials. In some

countries Reclaimed Asphalt Pavement (RAP) is commonly used for construction of road

pavements structural layers. Often limitations are applied in order to amount and type of

recycled materials. In this paper a new, innovative concept of asphalt structure for local roads

is proposed. In such structure each layer includes bio-origin material or materials from

recycling. Research work conducted under the “Use of eco-friendly materials for a new

concept of Asphalt Pavements for a Sustainable Environment” (APSE) project consist of

complex analysis of opportunities for application into each structural layer material from

recycling, including asphalt- origin materials. A proposed new structure will composed of

surface layer with bioethanol modified eco-asphalt. For interlayer increased amount of RAP is

going to be used due to application of bio-agent rejuvenating binder property. In non-asphalt

base layer material from infrastructure demolishing will be used, including demolished

cement concrete. In this paper test result of asphalt mixes composed with using of the bio-

agent and RAP are presented. It was proofed that higher than typical amount of RAP can be

applied for the production of asphalt mixture in traditional asphalt mix plant not equipped

with double barrel. Results proofed that bio-agent serves the role of rejuvenator in asphalt

mixture and allows for either application of higher RAP content of production of the mixture

in lowered technological temperature.


Impact of re-refined engine oil bottoms on binder properties and mix

performance on two pavements in Minnesota

ID: 284

Reinke, Gerald1, Hanz, Andrew

1, Anderson, R. Michael

2, Ryan, Mary

1, Engber, Steven

1,

Herlitzka, Douglas1

1 MTE Services, Inc., Onalaska, United States

2 Asphalt Institute, Lexington, United States

Topic: 2. Recycling

The use of vacuum distilled residues from the re-refining of used motor oils as blend stock in

paving grade bitumen has occurred in isolated markets in North America for more than 30

years. Recently in the United States the increasing need for low stiffness bitumen for use in

high binder replacement mixtures, coupled with economic considerations, has led to an

expanding market for these products. Little in-depth investigation into the long-term impact

of these additives on mixture performance has taken place until recently. Conflicting studies

from researchers in Canada and private organizations have been published. Here, we review

the eight-year performance of four virgin mixture test sections placed on a county highway

Minnesota. Three test sections used PG 58-28 bitumens from different crude sources, one of

which contained approximately 8% of the re-refined engine oil residuum. The fourth utilized

PG 58-34 polymer-modified bitumen. Pavement distress surveys were conducted over the

eight year period. Tests of the original bitumen following extended laboratory aging were

conducted. Properties of the recovered bitumen from eight-year-old field cores were

correlated to pavement distress. Double Edge Notched Tension (DENT) tests were conducted

on 20- and 40-hour PAV residues of the original bitumen. Iatroscan and extensive rheological

testing were conducted on laboratory aged bitumen and on bitumen recovered from laboratory

aged mixtures and field cores to determine the colloidal index, rheological index and the

extent to which laboratory aged and recovered bitumen materials were m-controlled. Also

evaluated were three test sections constructed at the Minnesota DOT MnROAD test site. A

comparative study of PG 58-28, PG 58-34 (PMA) and PG 58-40 (PMA +re-refined engine oil

bottoms) were evaluated over eight years. Bitumen used on the projects was tested as

described above. The PG 58-40 exhibited the worst performance. The results of binder

evaluations correlated to the fatigue cracking observed in the field with the test sections

containing the re-refined engine oil residuum exhibiting the most extensive fatigue cracking.

Based on this investigation we provide recommendations for test criteria to identify bitumens

that could increase an asphalt mixture’s likelihood to exhibit poor durability and fatigue

cracking performance.


Investigation of performance properties of laboratory and plant produced

bituminous mixture containing high rates of reclaimed asphalt

ID: 309

Sonmez, Ibrahim1, Yildirim, Seyit Ali

1, Temren, Zeliha

2

1 Istanbul Asfalt Fabrikaları Sanayi ve Ticaret A.Ş. (İSFALT), Istanbul, Turkey

2 Turkish Asphalt Contractors Association (ASMÜD), Ankara, Turkey

Topic: 2. Recycling

The use of reclaimed asphalt pavement (RAP) has gained considerable importance due to

increasing environmental concerns and economical aspects. There is interest in using higher

RAP contents and in using RAP in more mixtures. Although a large amount of asphalt from

damaged roads are reclaimed each year, only a small part of it can be up-cycled into a higher

value . The efforts have been towards increasing the RAP content by using rejuvenator and

efficient plant processes to comply with the requirements. The proper mix between old and

new materials, especially blending of binders is very important in the mechanical

performances of recycled asphalt mixture. In the framework. there is a need for investigation

of performance characteristics of laboratory and plant- produced recycled asphalt mixtures .

This paper presents an experimental study to evaluate the performance properties of

laboratory and plant-produced bituminous mixtures containing high rates of reclaimed asphalt

pavement (RAP) . The laboratory mixtures will be compared to plant produced mixtures to

evaluate the degree of blending between the virgin materials and RAP . The results of the

study will be also evaluated the performance of recycled mixture in comparison to virgin

bituminous mixtures in accordance with the requirements of the different asphalt pavement

layers. The study is carried out into two stages. In the first stage, dense graded bituminous

mixture containing 50% of RAP and special rejuvenator will be designed based on

performance characteristics of mixture in terms of permanent deformation, fatigue cracking

and moisture susceptibility. Additionally performance properties of the binders (virgin, RAP

and recovered) such as penetration, softening point, fraass breaking point, DSR before and

after RTFOT will be examined. In second part of the study, the same performance tests will

be performed on the recycled asphalt mixture produced in double drum batch type plant and

also recovered binder of the plant produced mixture.


Recycling of asphalt at the mixing plants in the Czech Republic

ID: 326

Varaus, Michal1, Hýzl, Petr

1, Stehlik, Dušan

1, Mondschein, Petr

2, Pazyna, Radek

3, Svoboda,

Petr4, Matoušek, David

4

1 Institute of Road Structures, Brno University of Technology, Brno, Czech Republic

2 Department of Road Structures, Czech Technical University in Prague, Praha, Czech

Republic

3 Froněk Ltd, Rakovník, Czech Republic

4 Road Contractors Association Praha, Praha, Czech Republic

Topic: 2. Recycling

The article deals with the recycling technology of asphalt done at the mixing plants in the

Czech Republic. The nowadays used methods are described. A greater attention is paid to the

technology with the use of pararell drying drum. This additional equipment, which can be

found only on 4 mixing plants in the Czech Republic, is able to preheat and add RAP in the

amount of up to 80 %. The research, which has been done with asphalt mixtures with various

amount of added RAP with the use of rejuvenators is described. The comparative

measurements, carried out with the use of functional tests as wheel tracking test, measurement

of stiffness modulus, fatigue and water sensitivity test are published.


Recycling of high percentages of reclaimed asphalt using a bio-rejuvenator – a

case study

ID: 334

Bocci, Edoardo1, 2

, Grilli, Andrea3, Bocci, Maurizio

2, Gomes, Vitor

4

1 eCampus University, Novedrate, Italy

2 Department of Civil, Building and Architecture Engineering, Università Politecnica delle

Marche, Ancona, Italy

3 Department of Economics and Technology, University of the Republic of San Marino, San

Marino, San Marino

4 Arizona Chemical, Almere, Netherlands

Topic: 2. Recycling

Worldwide, hot recycling of reclaimed asphalt (RA) has actually raised interest because of the

many advantages related to environmental issues. The benefit of reusing RA is associated not

only to the reduction of aggregate requirements and the preservation of natural resources, but

also to the reuse of aged bitumen from the RA, implying a reduction of the required amount

of virgin bitumen. However, the aged bitumen contained in the RA is typically oxidized and

hardened, leading to a fragile behavior in the pavement layers, especially when high amounts

of RA has to be recycled (more than 30% RA). For this reason, the use of specific additives is

strongly recommended in order to restore the desired bitumen properties and consequently

produce an asphalt concrete with the expected mechanical characteristics. This paper presents

the results from a trial section on the highway connecting Ancona to Perugia in the center of

Italy. An asphalt mixture, for a base course, containing 50% of RA and a bio-based

rejuvenator was characterized in the laboratory and then produced in a mix-plant and laid

down in the field for the final validation of the hot recycling process. The results shows that,

by using the rejuvenating additive, high percentages of RA can be reused in the production of

new asphalt concretes, maintaining good mechanical characteristics of the final mixture and

thus complying with the existing technical specifications.


Mix designs for cold recycled pavement materials considering local weather

and traffic conditions

ID: 357


1, Valentin, Jan

2, Čížková, Zuzana

2, Suda, Jan

2,

Batista, Fátima3, McNally, Ciaran

4

1 Department for Road Construction and Maintenance, University of Kassel, Kassel, Germany



3 Laboratório Nacional de Engenharia Civil, I.P., Lisabon, Portugal

4 University College Dublin, Dublin, Ireland

Topic: 2. Recycling

Cold recycling is a road rehabilitation procedure/technique, where the reclaimed road material

from rehabilitated pavements is recycled completely and used in the new structure with only

small contents of new road materials. This is done preferably in-situ to save time, costs and

environment. However, internationally various mix design procedures were developed since

decades resulting in diverse contents of bituminous binders (emulsion or foamed bitumen)

and/or mineral binders (cement or hydraulic road binder). The different material compositions

result in diverse mechanical material properties and demand for different pavement designs.

Based on an international comparison of cold recycling experience, commons and differences

were elaborated during European CoRePaSol project funded by the CEDR. The existing

definitions of various cold recycled materials were assessed and supplemented in order to

introduce clear material definitions in future European specification documents. Based on

intensive test campaigns suitable assessment procedures are proposed to address these

materials. At the same time based on local traffic and weather conditions as well as

availability of source materials, a decision model is proposed for choosing the optimum cold

recycling material for the given rehabilitation project.


End-of-life strategies for cold recycled mixtures and the multiple recycling

approach

ID: 358


1, Valentin, Jan

2, Valentová, Tereza

2, Kotoušová,

Adriana2

1 Department of Road Construction and Maintenance, University of Kassel, Kassel, Germany



Topic: 2. Recycling

Cold recycling is a road rehabilitation procedure, where the reclaimed road material from

demolished pavements is recycled completely in the new structure with only small contents of

new road materials. Cold recycling is applied worldwide since several centuries but little is

known about end-of-life strategies for this kind of pavement materials. However, European

construction regulation demands for taking the recycling strategies into consideration already

during the mixture and pavement design phase. Therefore the multiple recyclability of cold

recycled materials was analyzed during European CoRePaSol project. Therefore, artificially

aged cold recycled material was prepared in laboratory in order to simulate end-of-life

characteristics of these road materials. On these material options for multiple cold recycling

as well as the application of hot and warm recycling in new asphalt mixtures was analyzed

designing suitable mixes with reduced binder content and RAP content of up to 30 %. The

results indicate that cold recycled pavement layers can be rehabilitated again by applying cold

recycling at least once. However, each applied cold recycling cycle will raise the bituminous

binder content which may lead to lower stiffness and reduced resistance against permanent

deformation. It is necessary to focus more intensively on combining these approaches with

rejuvenation and better reactivation of the used bitumen. Nevertheless the cold recycled

material also can be recycled in new warm and hot-mix asphalt where the bitumen originating

from the initial asphalt pavement as well as from the applied cold recycling cycles can be

reactivated in future. Here common recycling strategies can be applied without the need for

modifications. As a result, the recyclability of cold recycled materials is similar to the

recyclability of road layers composed of hot-mix asphalt and don’t indicate a constraint

against the application of this methodology in pavement rehabilitation.


Laboratory Evaluation On Waste Slag Produced Zinc Industry As Mineral

Filler In Stone Mastic Asphalt

ID: 383

Aktaş, Bekir1, Aslan, Şevket

1

1 Civil Engineering, Erciyes University, Kayseri, Turkey

Topic: 2. Recycling

To provide sustainable development, environmental and economic issues have encouraged to

researchers to investigate reuse of the waste materials in some fields. Road construction is an

important sector owing to need more materials and to evaluate recycling waste materials in

comparison with other fields of civil engineering. The purpose of this study is to investigate

usability of waste slag produced zinc industry as mineral filler in Stone Mastic Asphalt

(SMA). Waste slags were added to mixture as a mineral filler replacement with conventional

aggregate to produce SMA specimens. The same gradations of mixtures were produced using

normal crushed aggregate as control samples. The Marshall mix design system was used for

sample preparation in accordance with Turkish specifications. The SMA specimens, made of

waste slags and conventional asphalt concrete, were evaluated through their fundamental

engineering properties such as Marshall stability, flow tests and resistance to moisture-

induced damage tests. The results indicate that the application of waste slag as mineral

aggregate improves the Marshall stability and flow performance but it influences the

performance of moisture-induced damage negatively.


Recycling reclaimed asphalt in Flanders: state of the art 2014

ID: 385

Van den bergh, Wim1, Seghers, Dieter

2, Anthonissen, Joke

1, Vuye, Cedric

1, Benor, Timy

1,

Haulet, Jean-Philippe1

1 Research Section Energy and Materials in Infrastructure and Buildings, University of

Antwerp, Antwerpen, Belgium

2 Flemish Agency for Roads and Traffic, Flemish Road Adminstration, Brussels, Belgium

Topic: 2. Recycling

This contribution illustrates the state of the art of the use of reclaimed asphalt pavement

(RAP) in bituminous mixtures for roads in Flanders. A first part will give a summary of the

supply of reclaimed asphalt and its use for the last decade in Flanders. Different mixtures with

the use of RAP are compared by means of stiffness and fatigue properties. In Flanders, the

regulation and the composition of asphalt is different for non-public and public works. For the

latter, the Flemish Regulation must be followed and till 2011 recycling was allowed both for

mixtures for base and surface layers, up to 50% binder substitution. However, after 2011

recycling became prohibited for top layers. Since 2013, the Flemish Agency for Road and

Traffic and the University of Antwerp started an experimental program to evaluate the limited

use of reclaimed asphalt in mixtures for surface layers, e.g. AC-10 and SMA. A LCA study

showed that the use of RAP is beneficial compared to the use of warm mix asphalt. Further, in

this paper, the results of this experimental program for AC-10 and SMA with RAP are

discussed. The study recommended allowing the use of RAP up to 50% for AC-10. In a

second project, the performance characteristics of SMA mixtures (SMA-C1 with 70/100 and

SMA-C2 with 45/80-50) with reuse of reclaimed asphalt pavement are explored. The

experimental study of the performance characteristics consist of % Voids, resistance to water

sensitivity, rutting, stiffness modulus and ravelling (Darmstadt scuffing device prTS12697-

50). The study showed that the addition of RAP has no negative effect on the performance of

the mixtures. The contribution concludes with a recommendation to re-evaluate the

prohibition of RAP in surface layer mixtures.


3. Maintenance and Application techniques

Education and training of roller operators contributing to durable and

sustainable asphalt pavements

ID: 9

Beuving, Egbert1, Luby, Martyn

2

1 EAPA, Brussels, Belgium

2 Volvo Construction Equipment, Eskilstuna, Sweden

Topic: 3. Maintenance and Application techniques

Compaction of the pavement structure and the asphalt mixtures degree of compaction are very

important for the durability and the behaviour of asphalt pavements. However in general there

is a lack of understanding of the importance of the work of the roller operator. Nowadays

many companies rent rollers and some companies have no own rollers anymore. When

renting equipment one could ask a truck driver to drive a roller and here the problem will

begin. In an asphalt crew all tasks are important, but the role of the roller operator is often

underestimated. The main problem is that the management often does not see the importance

of what roller operators are contributing to the quality of the finished asphalt layer. A good

education system for roller operators with a certificate or licence to operate a roller could help

to underline the importance of good compaction. A good education of the roller operator will

also improve his/her image and this better image could help to attract more young people to

the industry. Having an operators’ licence or certificate for roller operators might be a way to

achieve a better education of roller operators. In some countries they already have certificates

for roller operators, but that is mainly for safety reasons. Next to improving the recognition,

status and attractively of the job by good education, licencing could also give the roller

operators a value on the market, it could give them mobility in the branch and it would also

give the contractors an assurance (of knowledge) when hiring them. Education and training of

operators can also lead to significant cost reductions. By adjusting the operators’ behaviour

and by using the equipment in an optimal way large savings in both fuel consumption and

maintenance costs are achievable. So good education is very important and every Euro

invested in education will pay itself back.


Novel Heating Technologies to Control the Surface Conditions of Pavements

ID: 16

van Wijk, Ron 1, Sangiorgi, Cesare

2, Baroncini, Francesco

2

1 GFSC Consultants and Engineers BV, Arnhem, Netherlands

2 Civil. Chemical, Environmental and Materials Engineering, University of Bologna,

Bologna, Italy


In winter roads become slippery due to the influence of snow and ice. Despite traditional

snow ploughs and salt sprinkling, statistics show that this results in the loss of many lives

each year and causes severe material damage. Furthermore it disrupts traffic, causing

significant economic damage. Winter conditions also accelerate the deterioration of asphalt,

especially open structured surface layers, resulting in extra maintenance costs for road

authorities. Dutch based GFSC Consultants and Engineers, Grontmij, Reef-Infra and AHT

Netherlands, united in the Heated Roads consortium, therefore have developed an alternative

for combating the adverse effects of ice and snow on roads. It uses an innovative electric

infra-red heating system that consists of a very thin coated metal alloy strip that is placed

under the top asphalt layer (or binder). Due to its special amorphous molecular structure, it

heats up the asphalt monolith structure very rapidly and is also energy effective. Several test

sections were built in Germany, Italy (in cooperation with the University of Bologna) and The

Netherlands in order to study the effect of the ribbons on the deicing of the surface as well as

on the extension of the lifetime of the asphalt structure. Several parameters were varied such

as the distance between and depth of the ribbons, the use of insulation material and the

generated power by the ribbons. Also test were done related to the application procedure, like

prefixing the ribbons onto asphalt grids in order to speed up the application process. The

research was supported by the Dutch Provinces of Gelderland and Overijssel and rewarded a

subsidy by the European Union as this innovation is as a new way to secure the safety on

roads, to guarantee traffic flow and to extend the lifetime of asphalt (and thus reducing

maintenance costs).


Effectiveness of preventive maintenance of asphalt pavements

ID: 19

Sebaaly, Peter E.1, Hajj, Elie Y.

1

1 Civi & Env. Engr., University of Nevada, Reno, Nevada, United States


In light of shrinking agency budgets, pressure is being placed on agencies to become more

cost-effective in their delivery of services to the public. Unfortunately, transportation

infrastructure, by nature, begins to deteriorate as soon as it is placed. Roadway preventative

maintenance provides users with safer and more comfortable rides and has been shown to

reduce overall transportation costs when maintenance treatments are properly selected and

timed. As such, infrastructure agencies have expressed an increasing interest in the selection

and timing of maintenance activities for their existing transportation infrastructure. The paper

presents the evaluation of field performance of asphalt pavements with sequential slurry seal

applications. the study developed performance models for asphalt pavements without slurry

seals and asphalt pavements receiving slurry seals at various times following construction,

and identified the optimum time for the application of slurry seals on asphalt pavements. This

was achieved by evaluating the long-term pavement performance data collected using the

MicroPAVER system for the last 15 years and the cost-effectiveness of slurry seals applied to

new and existing flexible pavements at years 0, 1, 3, 5, 7 and 9 after construction. This study

found that the application of the slurry seal immediately after or 1 year after construction of

the asphalt layer is not effective in terms of both the benefit to the users and the benefit cost

ratio for the agency. The optimum time of application of slurry seal depended on the type of

the construction activity. For newly constructed pavements, the optimum time to apply slurry

seal was three years after construction. For pavements subjected to overlays, the optimum

time to apply slurry seal was between three and five years after construction. However, for

uniformity purposes, it was recommended that the agency applies slurry seal three years after

the construction of the asphalt layer for both new and overlay constructions.


Best practices for crack treatments in asphalt pavements

ID: 45

Decker, Dale Steven1

1 Dale S. Decker, LLC, Eagle, Colorado, United States


Treating cracks in asphalt pavements is a major part of every maintenance engineer’s work.

The objective of any crack treatment is to minimize the intrusion of water into underlying

layers of the pavement structure. Such water infiltrates the base layers of the pavement and

may lead to pavement structural failures. Crack treatments fall into two broad categories –

crack sealing and crack filling. Crack sealing is generally performed on “working” cracks.

Crack filling is generally performed on “non-working” cracks. The objective of this project

was to review the state-of-the-art in crack treatments through a literature review, establish the

state-of-the-practice regarding construction techniques based on an extensive survey of

agencies and contractors, and to develop a Best Practices guideline that will improve the

effectiveness of crack sealing and crack filling. This report addresses only the Best Practices

guidelines for crack sealing and crack filling. The work was part of NCHRP Project 20-07,

Task 339 which was recently completed by the author.


Workability of asphalt mixtures

ID: 57

Poeran, Natascha1, Sluer, Berwich

1

1 QRS, Boskalis Nederland, Nieuw Vennep, Netherlands


The construction of an asphalt concrete pavement is an affair that requires collaboration

between a number of disciplines. Logistics, transport and workmanship are key words in

making these alliances successful. Especially, because the temperature dependent behavior of

asphalt concrete mixtures hamper the realization of high-quality pavements. Paving at too

high or too low temperatures for example, could lead to difficulties during compaction. The

inflow of asphalt concrete at optimum paving temperatures thus is a vital first step in the

paving process. However, this is very much related to the logistic process,type and accuracy

of transport. Fortunately, conventional asphalt concrete mixtures containing penetration

bitumen are relatively less sensitive to these types of irregularities. Particularly because

skilled asphalt workers can employ their extensive experience with these mixtures. By doing

so, they can adequately and timely respond to unexpected circumstances enabling them to

ensure the quality of the asphalt concrete pavement. Recent developments in asphalt concrete

mixture design and bitumen composition though, have caused quite an increase in the number

of available asphalt concrete mixtures. As a result asphalt workers cannot entirely rely on

their experience during paving and compaction anymore. The determination of an asphalt

concrete’s workability in relation to temperature could therefore contribute enormously to the

overall asphalt process, from production to construction. Clearly appointing the most

favourable temperature windows for paving and compacting of an asphalt mixture will lead to

more efficient logistics, proper paving, correct compaction and equally as important to a sense

of satisfaction with the asphalt workers. All will result in higher quality asphalt concrete

pavements. To determine the workability of asphalt mixtures a prototype measuring device

was developed based on findings from previous research on workability. This new prototype

registers the torque exerted on a paddle, while this paddle stirs through a cooling asphalt

concrete mixture. The development of the measured torque provides a (relative) indication of

a mixture’s workability. In an exploratory research program the most suitable test conditions

and mixing configuration are determined by testing a variety of asphalt concrete mixtures and

bitumen. The results of this research are reported and discussed throughout this paper.


Field study to evaluate different pre-normative interlayer adhesion tests

ID: 95

Destrée, Alexandra1, De Visscher, Joëlle

1, Vanelstraete, Ann

1

1 Division Asphalt Pavements, Bituminous Applications and Chemistry, BRRC, Sterrebeek,

Belgium


An effective and durable bond between the various constituent layers is an absolute

prerequisite for the durability of a road pavement. To ensure the adhesion between successive

road construction layers, cationic bitumen emulsions are the most frequently used type of tack

coats. Several tests are currently available to evaluate the bonding performance between

layers based on different loading modes (shear, torque and tensile) They vary in regard of test

devices, test temperature, loading mode as well as sample geometry and preparation and

hence they lead to different results. In this context, the European standardisation committee

CEN TC227/WG1/TG2 “Test methods for bituminous mixtures” has developed a prestandard

prEN12697-48 “Bituminous mixtures – Test methods for hot mix asphalt – Part 48: Interlayer

Bonding” for the determination of interlayer bond strength where three main normative test

methods are considered: tensile adhesion test (TAT), shear bond test (SBT), torque bond test

(TBT). A site test method to evaluate the tensile bond strength making use of a practical

clamping device and used for many years in Quebec, called layer adhesion measuring

instrument (LAMI), was recently included in the prestandard. This article gives an overview

of the different methods and discusses the results of a study in the laboratory (SBT, TAT) and

on site (LAMI) in which these pre-normative interlayer adhesion tests were used. The study

leads to recommendations for the methods described in prEN 12697-48 and shows the

differences between the methods. The ultimate aim of this study is to come to

recommendations for improving the adhesion performance of multilayer pavements and to

propose values for minimum interlayer bond strength to be achieved on site.


Economically effective revitalization of portland cement concrete pavements

by asphalt layers overlay

ID: 107

Špaček, Petr1, Hegr, Zdeněk

1, Varaus, Michal

2, Hýzl, Petr

2, Kaděrka, Robert

3

1 Skanska a.s., Praha, Czech Republic

2 Brno University of Technology, Brno, Czech Republic

3 PavEx Consulting, s.r.o., Brno, Czech Republic


This paper describes experiences and results gained from common research project of Brno

University of Technology and Skanska a.s., which was co-financed by Technology Agency of

the Czech Republic. The purpose of this research project was to develop more effective

processes and approaches in field of revitalization of the old Portland Cement Concrete (PCC)

pavements by asphalt layers overlay. The main focus was concentrated on areas like

optimization of PCC pavement segmentation step, development of high performance Stress

Absorbing Layer (SAL) for mitigation of reflective cracking and development of

methodology for asphalt layers overlay pavement design. In this paper, there are presented

results of the field tests by Falling Weight Deflectometer (FWD), results of laboratory tests of

asphalt mixtures for Stress Absorbing Layer application like Wheel tracking test (EN 12697-

22), Bending beam test and Relaxation test as well as a results and experiences about carrying

out of experimental trail sections. In field of SAL mix design and laboratory testing, there

were compared different types of high performance asphalt binders like polymer modified

bitumen and crumb rubber modified bitumen.


An investigation into the effects of tack coat application rate on interlayer

shear bond strength

ID: 118

Saba, Rabbira1, Hovin, Wenche

2, Jørgensen, Torbjørn

1

1 Road Technology, Norwegian Public Roads Administration, Trondheim, Norway

2 Central laboratory, Norwegian Public Roads Administration, Trondheim, Norway


As part of a research and development project which aimed at improving the service life of

pavements and which was conducted by the Norwegian Public Roads Administration, an

investigation was conducted into interlayer bond strength. The purposes of the investigation

were to find out if the current requirements regarding tack coat are satisfactory and to

determine appropriate bond strength values that can be used as basis for improved

requirements. The work involved both field and laboratory testing in which first

measurements of tack coat application rates on normal paving projects were conducted and

analysed. Then varying quantities of tack coat, with three targeted levels, were applied on

selected test roads with two texture levels. The amount of applied tack coat was measured and

after completion of the paving, core samples with 100 mm in diameter were taken from the

test roads. The samples were tested in shear bond test (SBT) in accordance to prEN 12697 -

48. The results from this study indicated that the effect of the quantity of tack coat depends on

the surface characteristics of the underlying layer. For smooth surfaces increasing application

rate resulted in decreasing shear bond strength. For rough surfaces, the results indicated little

or no correlation between tack coat application rate and shear bond strength.


Life-prolonging preventive maintenance techniques for porous asphalt

ID: 128

The, Peter1, Voskuilen, Jan

1, Ven, Martin van de

2

1 Rijkswaterstaat, Ministry of Transport and the Environment, Utrecht, Netherlands

2 Delft Technoical University, Civil Engineering, Delft, Netherlands


The Dutch national roads agency Rijkswaterstaat (RWS) is constantly looking for faster

maintenance techniques and more cost effective maintenance measures, to extend the service

life of Porous Asphalt (PA) with minimal traffic hindrance. End of service life of PA is

determined by excessive loss of stones from the surface, called raveling. Raveling is caused

by a complex of factors like possible drainage of the mortar (transport, construction, early

life), direct loading via the stones, water pressure under the tire, accelerated ageing from the

surface, clogging, etcetera. In the field raveling mainly occurs after the bitumen in the top of

the PA layer is strongly aged. Due to the ageing of the bitumen, the mortar bonding bridges

between the coarse aggregate become more brittle, which makes them more sensitive for

(micro) cracks and/or adhesion loss between stone and the mortar, which probably will lead to

raveling. The service life of existing PA could be extended by adding bitumen from the

surface, which could fill and heal micro-cracks, rejuvenate the aged bitumen in the mortar and

add bitumen to the mortar bonding bridges. RWS has challenged the Dutch market to develop

life-prolonging preventive maintenance techniques for PA. Three potential rejuvenating

products, that could fulfill the requirements of RWS, were offered: - Pentack® of producer

ESHA (emulsion system), applied by ESHA - Modiseal® ZX of producer Latexfalt (hot

polymer modified bitumen), applied by contactor BAM - Modimuls® ZV of producer

Latexfalt (emulsion system), applied by contractor Heijmans. Whether these products actually

contribute to the life extension of PA is investigated by InfraQuest (a partnership between

RWS, Delft University of Technology and TNO). The three products were applied on existing

PA road sections, which were not raveled, and extensive research was conducted on

specimens obtained from these test sections for validation. Also a Life Cycle Analysis and

Cost Benefit Analysis were performed to investigate whether the examined life extension

maintenance measures were cost effective and satisfied the environmental requirements of

RWS. In this paper an overview will be given of the approach to the validation studies and the

conclusions that could be drawn from the results.


The influence of asphalt workmanship on pavement service life

ID: 130

Aurstad, Joralf1, Uthus, Nils S.

1, Telle, Roar

2, Bakløkk, Leif J.

1

1 Norwegian Public Roads Administration, Trondheim, Norway

2 Veiteknisk Institutt, Høvik, Norway


The “Durable Roads” program 2011-2014 has been a 4-year research program conducted by

the Norwegian Public Roads Administration (NPRA). The overall objective is to increase

service life and reduce annual costs for the Norwegian road network. For many years there

has been a strong need in Norway for improved expertise in the area of road technology and

road maintenance. Premature failures /distresses occur too often also on new roads. Focus on

cost and completion time often leads to low quality work, improper use of materials is often

seen, and there is a growing lack of professionals. “Durable roads” has looked especially into

how to improve asphalt pavement quality and thereby achieve longer service life. The paper

shows typical damages that may occur on the road due to wrong or inadequate execution of

asphalt works, and insufficient quality control. Further the paper presents initiatives and

measures that have been taken in this respect and how these now are being implemented in

NPRA. Among the tools that hopefully will contribute to longer lasting pavements in the

future are; - Practical control schemes/check lists/instructions for NPRA’s inspectors - New

“Best practice guide” developed for both contractors, road owners and for education purposes

- New guidelines for asphalt transport by boat (up to 30 % of asphalt mix is transported by

boat in Norway) - Use of IR-cameras to promote and document homogenous

conditions/temperatures during laying and compaction - Introducing competence/skill

requirements in contracts and tender documents - Introducing a new non-destructive method

for detecting deviations in quality on new asphalt pavements, based on laser measurements


Design and industrial application of a microsurfacing pavement based on non-

Venezuelan bitumen.

ID: 213

Giorgi, Claude Emmanuel1, Loup, Frédéric

2, Simard, Delphine

2, Thomas, Jérémy

3

1 Technical Management, EIFFAGE Travaux Publics, Neuilly/Marne, France

2 Central Laboratory, EIFFAGE Travaux Publics, Corbas, France

3 Regional Laboratory, EIFFAGE Travaux Publics, Le Haillan, France


The study presented in the paper focuses on the design of the next generation of

microsurfacing pavements. This technique consist of applying in-situ a thin layer of a cold

mix in order to regenerate the macro texture and the waterproofing of an aged wearing course.

This technique has been getting bigger every year for the last 20 years, especially in France

where more than 50 million square meters are applied every year. This technique relies on the

use of asphaltenic bitumen from Venezuela to get fast cohesion built up and minimal impact

on traffic. For years, many alternatives were studied to replace Venezuelan bitumen, with

different results, but still Venezuelan bitumen was preferred to get the best quality. In 2014,

Eiffage’s central laboratory worked on a brand new microsurfacing design, based on the use

of a special chemistry, enabling the use of any type of bitumen to get the same results of the

one coming from Venezuela. To be able to achieve such a performance, a new methodology

was set up to characterize in a more effective way properties of the new design. The same

year, first jobsites were laid down using this new technology, covering more than 150 000

square meters of roads. In 2015, this new design was generalized and more than 800 000

square meters were laid down.


Structural resistance and interlayer bonding of bridge-deck systems

ID: 228

Angst, Christian Dr.1, Raab Christiane, Dr

2


2 EMPA-Swiss Federal Laboratories für Materials Science and Technology, Dübendorf,

Switzerland


Bridge-deck systems on concrete bridges are complex systems which have to meet many

requirements. Such systems must act as a protective layer against water and de-icing salt as

well as withstand temperature fluctuations and traffic loads which are worsened by the

channelling of traffic on bridges into narrower lanes. The research packaged had the

following research aims: • to evaluate and rank testing methods for assessing structural

resistance on several bridge-deck systems • to identify deformation-prone layers or materials •

to develop a procedure to give information on the long-term behaviour of the bonding

between sealing and concrete. Several bridge deck systems with different sealing products

(waterproofing material PU, and PMMA as well as polymer modified bituminous

waterproofing membrane) on different concrete subbases (different void content and surface

treatment) were tested by different test methods, such as rutting test with the Model Mobile

Load Simulator MMLS3, cyclic compression test, dynamic shear test and dynamic tensile

test. The results will be presented and discussed.


A proposed new design method for bituminous surface treatments

ID: 268

Sağlık, Ahmet1, Demir, Birol

1, Güngör, Ahmet Gürkan

2

1 Research and Development Department, General Directorate of Turkish Highways, Ankara,

Turkey

2 Inspection Board, General Directorate of Turkish Highways, Ankara, Turkey


Bituminous Surface Treatment (BST) is single or double application of binder and chipping

on prepared granular base or existing chipping layer or old asphalt concrete for preventive

purposes. In Turkey, BST is widely preferred because of relatively lower cost and faster

construction than those of conventional asphalt concrete. There are a few BST design method

in the world and all are basically derived from first design method proposed by Hanson. UK

design method has been used for about 50 years in Turkey. The long years experiences of

BST applications has been revealed the need for new design method since the existing design

values significantly need to be modified in the field. This paper proposes a new design

method, namely “KGM Design Method”, for single and double surface treatments

considering laying season as well as Average Least Dimension of Aggregate, climate, surface

characteristics, aggregate and binder properties.


Self-healing of asphalt mixes, containing conductive modified bitumen, using

microwave heating

ID: 288

Pérez, Ignacio1, Agzenai, Yahya

2, Pozuelo, Javier

2, Sanz, Javier

2, Baselga, Juan

2, García,

Antonio1, Pérez, Vicente

1

1 Technical Department, Cepsa, Alcalá de Henares, Spain

2 Dpto. Ciencia e Ingeniería de Materiales e Ingeniería Química, Universidad Carlos III de

Madrid, Leganés, Spain


In this paper we propose the use of carbon nanotubes as new additives for bituminous

materials suitable for microwave radiation heating. As self-healing rates of asphalt pavement

increase with temperature, these microwave absorbing materials facilitate crack healing.

Different modified bitumens, were prepared using high shearing rates to ensure adequate

dispersion. Carbon nanotube content and irradiation time were optimized measuring the

temperature-time profile for a selected set of specimens and an exhaustive study of the

rheological properties of the modified bitumens was carried out. Different tests performed

both on the modified binders and on asphalt mixes using microwave irradiation confirm that

high healing rates are obtained with low additive contents. Results showed in this paper have

been obtained in the development of the MAMCE project, granted by the Spanish “Ministerio

de Economía y Competitividad”, call “Innpacto 2011”.


Monitoring The Condition of Surfacing Seals With Nondestructive Tests at

Field

ID: 289

Karasahin, Mustafa1, Gurer, Cahit

2, Saltan, Mehmet

3, Aktas, Bekir

4

1 Civil Engineering, Istanbul University, Engineering Faculty, Istanbul, Kucukcekmece,

Turkey

2 Civil Engineering, Afyon Kocatepe University, Engineering Faculty, Afyonkarahisar,

Turkey

3 Civil Engineering, Suleyman Demirel University, Engineering Faculty, Isparta, Turkey

4 Civil Engineering, Erciyes University, Engineering Faculty, Kayseri, Turkey


Surfacing seal is an asphalt pavement type preferred because of its simplicity of application

and economic viability. It enables waterproof surfaces for sub-layers and creates smooth and

high skid resistance for vehicles. Therefore, surfacing seals constructed on unbound base are

widely used such as New Zealand, Australia and South Africa. However the performance of

surfacing seals can be affected by a number of factors. If these factors are not considered, they

will need to be reconstructed after a very short period. In this study, performances of

surfacing seals under heavy traffic were observed for 2 years, and routine tests were

performed to determine the surfacing seal’s performance in relation to traffic and climate and

to determine the kind of deteriorations which occurred. In this study variety of test such as

sand-patch, British pendulum, density measurement with electromagnetic method, measuring

surface temperature with thermal camera, light weight deflectometer, dynamic cone

penetration test and layer thickness measurement were performed with ground penetrating

radar technique. The results of the study show that loss of macro texture, and raveling and

flushing are the most common types of deterioration especially at road sections with

longitudinal slope. Furthermore, skid numbers decrease during the rainy seasons when the

bearing capacity of layers also decreases, the trend of raveling deterioration decreases at roads

with high traffic volume and average maximum surface temperature. However, it was

determined that trend of flushing deterioration increase.


Australian airport asphalt surface treatments

ID: 306

White, Greg1, Thompson, Michael

2

1 Fulton Hogan, Brisbane, Australia

2 Fulton Hogan, Adelaide, Australia


Many airport surfaces in Australia are constructed of dense graded asphalt. These surfaces are

generally replaced by asphalt overlay every 10-15 years. Airport asphalt surfaces are highly

suited to sprayed surface preservation treatments. There are a range of treatments to preserve

and extend the life of asphalt surfaces. These generally replace lost binder and/or fine mineral

material. These treatments generally create a temporary protective coating over the existing

surface. A number of new materials have largely replaced the traditional coal-tar based and

cutback bitumen products. These new materials are emulsion based and often include

polymers. This paper presents a summary of experience and new materials for treatment of

asphalt surfaces at Australian airports. Oxidation retarders and surface filling treatments are

explored, as well as fuel resistant membranes. A number of lessons learnt are presented and a

whole of life approach is undertaken in considering future opportunities.


Self Healing Asphalt - Extending the service life by induction heating of

asphalt

ID: 310

van Bochove, Gerbert1

1 R&D, Heijmans Infra B.V., Rosmalen, Netherlands


Extending the service life of an asphalt surface layer is always a continuing desire. This can

be done by improving the quality of the product when laying. Another possibility is to

upgrade the quality throughout the service life. This is the method to Self Healing Asphalt.

The aging of asphalt under weather and traffic is associated with the formation of micro

cracks in the mortar fraction. By adding a conductive material in the asphalt production, such

as steel wool fibres, the possibility arises of heating up the mortar of the asphalt by an

induction device. A short "heat shot" through the steel fibres, causes melting of the

bituminous binder and because of that, hairline cracks in the asphalt layer are closed. The

asphalt mixture will "reset" and start a new life. This can be done several times during the

service life. In The Netherlands from 2010 several tracks have been laid with Self Healing

Asphalt. In 2014 also the first healing action on site was carried out. The results are

promising. This development for instance opens new ways to a broader application of noise-

reducing road surfaces. These surfaces are susceptible to damage from twisting movement of

traffic and therefore cannot be applied to many projects. By providing the most critical

locations with Self Healing Asphalt the quality during the life can be maintained by periodic

induction action. Also, making noisy expansion joints noiseless, this material can play an

important role. In the paper the principle of Self Healing as well as several applications will

be reported.


Effect of Aggregate Embedment On Chip Seal Retention Performance

ID: 317

Aktaş, Bekir1, Karaşahin, Mustafa

2, Saltan, Mehmet

3, Gürer, Cahit

4

1 Civil Engineering, Erciyes University, Kayseri, Turkey

2 Civil Engineering, Istanbul University, Istanbul, Turkey

3 Civil Engineering, Suleyman Demirel University, Isparta, Turkey

4 Civil Engineering, Afyonkocatepe University, Afyonkarahisar, Turkey


The aim of this study is to evaluate chip seal retention performance with two type of

aggregate depending on the various embedment depths using Accelerated Chip Seal

Simulation Device (HSKSC). To simulate the worst condition in field for chip seal in respect

to aggregate retention performance, the water was poured on the specimens and performance

tests were conducted in water. Major findings of this research include that increasing the

aggregate embedment significantly reduces the aggregate loss. However, it correspondingly

reduced the macrotexture value of the chip seal which is very important parameter for chip

seal service life.


Application of bitumen adhesion and cohesion laboratory tests in a finite

element modelling approach of chip seals

ID: 408

Gerber, Johan Andries Kritzinger1, Jenkins, Kim

1

1 Dept. of Civil Engineering, University of Stellenbosch, Matieland, South Africa


Chip seals are constructed throughout South Africa as the final layer on top of new or existing

pavements. The seal layer provides a waterproof cover for the underlying pavement and a

safe, all-weather, dust free riding surface for traffic with adequate skid resistance. The seal

layer protects the underlying layer from the abrasive and destructive forces of traffic and the

environment. The level of service provided by the seal is governed by its relations to various

surface distress types. Distress affects the seal’s ability to fulfil its functional and structural

requirements. Surface ravelling and fatigue cracking are two major distress types which annul

chip seal functionality. Bitumen adhesion and cohesion laboratory tests were therefore

conducted and subsequent transfer functions were developed which were utilized in the

response quantification of a chip seal finite element model. The response outputs of the finite

element models were quantified in terms of wheel load repetitions to the initiation of failure

for each distress type. A typical South African seal design assumption suggests a 40:1

equivalent damage ratio for light vehicles versus heavy vehicles. Quantification of the model

responses indicated a 3:1 wheel load damage ratio for ravelling and a 2:1 ratio for fatigue

cracking. The response model can therefore be utilized as a tool in facilitating the seal design

process.


Guidance for the selection of pothole repair options

ID: 422

McHale, Michael1, Nicholls, Cliff

1, Carswell, Ian

1

1 TRL Ltd, Edinburgh, United Kingdom


Potholes are a major problem in many parts of the world. The approach to the repair of these

defects is varied because they occur on different types of road and their causes can be very

different. As a result, many different techniques and products are offered for the repair of

potholes, all of which have advantages and disadvantages. The relative effectiveness of the

different techniques and products can vary from site to site. This paper describes a Scottish

study that aims to provide a consistent approach to selecting a pothole repair material or

technique from treatments currently available. The new guidance is based on consultation

with a range of practitioners from Scottish road authorities involved in repairing potholes. The

resulting discussions and information gathering led to the development of ideas for the

selection process outlined in the guide. A simple procedure utilising flowcharts has been

developed to assist users to identify an appropriate pothole material or technique to treat

potholes located in different situations. Whilst it is impossible to identify the unique “best”

option for each situation, it is intended that the guidance will lead to the most appropriate

option being selected.


4. Health, safety and Environment

Works For Increasing Skid Resistance At The Highways In Turkey

ID: 52

Orhan, Fatma1

1 General Directorate of Highways, Ankara, Turkey

Topic: 4. Health, safety and Environment

Skid resistance is one of the most important features of road pavements. Road surfaces must

provide required skid resistance for the vehicles to facilitate safe driving distance in all

conditions. Skid resistance also has a direct impact on road safety. In the view of research and

development activities on bituminous binders and bituminous mixtures along with knowledge

and experience gained through road practices, it is specified the asphalt pavement with both

technically sufficient durability and high skid resistance level as well as compatible with the

conditions of Turkey. Following these studies, in order to increase the skid resistance of

Turkish Highways Network, major changes have been made in the Highway Technical

Specification. With the purpose of acquiring sufficient level of friction and texture on the

asphalt road surface, starting from the source of aggregate, physical characteristics and

gradation of aggregate, types of bituminous binder, mixture properties and surface

characteristics of asphalt pavement have been improved. In this paper, it is expressed the

improvements made in constituent materials of surface layers (aggregate, bituminous binder)

and mixture properties in order to increase skid resistance. Furthermore, it is also explained

the required surface characteristics of the newly constructed surface layers.


Noise reducing effect of new dense asphalt layers

ID: 53

Radenberg, Martin1, Drewes, Bianca

1, Manke, Ricarda

1



In recent years new asphalt surface layers have been developed to reduce traffic noise. The

noise-optimized asphalt surface layer (AC D LOA) has an adapted surface texture that causes

a decreased mature stimulus and permits lateral air displacement. This surface layer is

described in the new german technical regulation (E LA D). The porous mastic asphalt

(PMA) is a dense surface layer with a high void surface texture. It combines the advantages of

porous asphalts, due to their noise excitation, with the good durability of dense layers. A

working paper for its application is in process. To evaluate the stimulus of tire of different

asphalts a three-dimensional measurement of the surface texture is taken. Texture profiles

with many peaks cause strong mature stimulus, flat profiles with venting options have a noise

reducing effect. Another noise reducing mechanism is the compliance, which is quantified by

the mechanical impedance measured with an impact hammer. The compliance is mostly

influenced by the composition of the asphalt (void content), type and amount of bitumen and

the test temperature. Low mechanical impedance values indicate a reduction of the tire-road

noise. By these findings the mentioned noise reducing asphalts have been improved.


Asphalt mixture fire performance at full scale. PAVIREX project

ID: 62

Pérez, Ignacio1, Barral, Marisol

2, Romera, Ramón

2, Garrido, Fernando

3, González, Celestino

4,

Álvarez, Inmaculada4, Muñoz, María Eugenia

5, Santamaría, Antxón

5, Palmillas, Zita

5,

Villanueva, Sara6

1 Technical Department, Cepsa, Alcalá de Henares, Spain

2 Campezo Obras y Servicios S.A, San Sebastián, Spain

3 TST, Siero, Spain

4 Universidad de Oviedo, Oviedo, Spain

5 Polymat UPV/EHU, San Sebastián, Spain

6 Tecnalia, Azpeitia, Spain


Most roads and tunnels in Europe use asphalt mixtures as upper layer due to their excellent

properties, but the fire performance of these materials has been always a subject of discussion.

In this paper the study of the fire performance of different asphalt mixes (conventional and

modified with different aditives) is reported. The study was carried out at laboratory and full

scale. Asphalt mixtures were evaluated at laboratory level using two different tests: The cone

calorimeter test, as described in the ISO 5660, and a new test developed to study fire

propagation in asphalt mixtures slabs. Then, the best rated modified mixture and the

conventional one were tested at full scale using different fire loads in the San Pedro de Anes

test tunnel (Asturias, Spain). The main conclusion obtained from the different tests carried out

during this four years project is that there is no fire propagation over asphalt mixtures, but a

surface degradation in those zones were, due to an external heat source (> 400 ºC), asphalt

burns. Results showed in this paper have been obtained in the development of the PAVIREX

project, granted by the Spanish “Ministerio de Economía y Competitividad”, call “Innpacto

2011”.


Asphalt pavement wear by studded tires – Effects of aggregate grading and

amount of coarse aggregate

ID: 72

Snilsberg, Brynhild1, Saba, Rabbira Garba

1, Uthus, Nils

1



Studded tires cause mechanical wear of asphalt pavements in the northern European

countries, which leads to substantial problems with air quality and noise in urban areas.

Experience show that the pavements wear resistance is among other factors dependent on

amount and maximum size (D) of the coarse aggregate (> 4 mm). To reduce noise from

pavements, one measure is to reduce the maximum aggregate size (D) in the pavements.

However, this can increase the production of particulate matter from pavement wear. In this

study, the effects of maximum aggregate size (D) and amount of coarse aggregate on

pavement wear were investigated using a large-scale indoor Road simulator operated by the

Swedish National Road and Transport Research Institute (VTI) and small-scale asphalt testing

equipment (Prall) at The Norwegian University of Science and Technology (NTNU). Two

types of asphalt pavements were tested; asphalt concrete (AC) and stone mastic asphalt

(SMA). This study has clearly shown that the lower the aggregate size, the lower is the wear

resistance of the asphalt pavement and the higher is the dust production. In addition, SMA

pavements are more resistant to wear by studded tires compared to AC pavements due to the

higher amount of coarse aggregates contained in SMA mixes. The Norwegian Wear

Parameter (NWP) is used in this study as an indicator of the wear potential of different asphalt

pavements.


Innovative gussasphalt for noise reduction

ID: 94

Ripke, Oliver1, Ehlert, Stefan

2

1 Federal Highway Research Institute, Bergisch Gladbach, Germany

2 Strassen.NRW, Gelsenkirchen, Germany


The initial research focus to reduce traffic noise in Germany had been placed on porous

asphalt and was subsequently switched to dense pavements. An innovative approach to

optimise these surfaces is the so called Porous Mastic Asphalt (PMA). The basic idea behind

this construction method is the forming of a dense bottom zone of the surface layer, i.e.

similar to Gussasphalt (mastic asphalt), whereas the upper smaller zone of the layer has a

porous structure with good acoustic properties. First test sections on motorways and some

bridges were carried out in combined research activities of the state road administration,

research facilities and industry. An in depth investigation was carried out in the

interdisciplinary research project “Quiet Road Traffic 3” which included the optimisation of

the mix design and visualisation of the homogeneity with the help of X-Ray computer

tomography. The measurement of the skid resistance and acoustic emission were further

points of interest. The analysis of the data indicates that the concept is very promising, but a

few problems have to be solved. This includes the procedures in the laboratory and how to

control precisely the different zones of the layer (dense on the bottom, porous on top).


Laboratory evaluation of emissions from asphalt binder and mixes using a bio-

rejuvenating agent

ID: 116

Porot, Laurent1, Scott, Donald

1, Gaudefroy, Vincent

2


2 IFSTTAR, Institut Francais des Sciences et Technologies des Transports , de

l'Amenagement et des Reseaux, Nantes, France


With the constant focus on health and safety, the paving industry is paying close attention to

material emissions, particularly the fumes that are generated during the manufacture of Hot

Mix Asphalt (HMA); this may impact occupational exposure limits. In recent years, a

spotlight has been placed on bitumen fumes, and extensive studies have been published on

this subject. Concurrently, economic and environmental constraints require the development

of new technologies that use new products in asphalt mixtures. These constraints drive the

desire to incorporate high volumes of Reclaimed Asphalt (RA) in new pavement, which

requires specific engineered rejuvenating agents. On the downside, questions may be raised

regarding the impact of rejuvenating additives on emissions. This paper describes the impact

on fume emissions of a bio-based rejuvenating agent added to bitumen. An extensive

laboratory analysis was conducted on both binder and HMA. The binder evaluation was based

on analytical testing using headspace analysis combined with Gas Chromatography/Mass

Spectrometry (GC/MS). The static headspace of the binder was analysed and compared with

the analyses of binder mixed with two levels of the rejuvenating agent. The headspace of the

bitumen and bitumen/rejuvenator blends was evaluated over a range of temperatures typical

of HMA production and use. The asphalt mixture evaluation followed a methodology that

involves mixing the aggregates and binder in a closed pug mill and collecting fume samples.

The overall protocol includes four mixing sequences to mimic the entire process from mixing

at the plant to paving the road. This testing enables the detection of emissions of Total

Organic Compounds (TOC), which includes Polycyclic Aromatic Hydrocarbons (PAH). The

evaluations on the binders and mixes displayed similar trends and conclusions. The overall

results show that the incorporation of the bio-based rejuvenating additive did not contribute to

new components that affect occupational exposure limits, especially with regard to PAHs.


Cooperation in the field of skid resistance between Germany and the

Netherlands

ID: 143

Scharnigg, Karen1, Stöckert, Ulrike

1, Pinkofsky, Lutz

1, Bennis, Thijs

2, van Ooijen, Wim

2,

Vos, Erik2, Nugteren, Hans

2

1 BASt - Federal Highway Research Institute, Bergisch Gladbach, Germany

2 RWS - Rijkswaterstaat, Delft, Netherlands


The Netherlands is on the way to change its existing skid resistance measuring method for its

highway network from the Dutch RAW 72, a longitudinal force method, to the Sideway Force

method. This method is described in the Technical Specification 15901-8 (SKM device) as

well as 15901-6 (SCRIM device) and is in use in 9 European countries. The CEN TC 227

WG5 on Surface Characteristics is currently working on combining of these two technical

Specifications into a European standard for Sideway-Force (SWF) measurement devices. The

idea of this change in the Netherlands was perceived in 2013 and since then a lot of meetings

have been held with the different Dutch decision makers as well as with countries which

currently operate SWF devices. There was an intensive exchange of knowledge about these

devices and their corresponding quality assurance systems, because the Netherlands wanted to

incorporate and rely on an existing system of a neighbor country without losing their present

level of quality. The Netherlands has therefore decided to incorporate the German SKM

approach. The network monitoring with the new system will start in 2017. To ensure the

quality of skid resistance measurements and further cooperation in this field, it has been

decided to initiate an alliance between BASt and the Dutch road owner Rijkswaterstaat

(RWS). This alliance will facilitate an exchange of research activities, calibration of the Dutch

systems according to the existing German Standard as well as control measurements with a

BASt-device on the Dutch network during the network monitoring. During 2016 also

comparative measurements will be performed on a network level with the current Dutch

device and with an SKM device to determine a conversion between the two and to be able to

define new threshold values.


Transfer of the IARC monograph on bitumen in European ways of working

ID: 145

Rühl, Reinhold1

1 German Bitumen Forum, Frankfurt, Germany


In Germany, the DFG Senate Commission (MAK Commission) and the Committee on

Hazardous Substances (Ausschuss für Gefahrstoffe, AGS) scientifically evaluate and rank

substances with regard to possible carcinogenic effects. In many European states the decisions

and recommendations of the MAK Commission are a substantial basis for classifications. In

Germany, the Federal Ministry of Labour and Social Affairs implements the classification of

the AGS by publication in national law. Following the publication of the IARC monograph

"bitumen and emissions from bitumen" the MAK Commission and afterwards the AGS will

review their existing classifications. In the technical chapter of the IARC monograph also

methods and materials which are not used in Germany or Europe are covered. Therefore, the

German Bitumen Forum has made a transfer of the technical chapter on European practise

and standards, thus the MAK Commission may take into account the working methods and

materials that are common in Europe. Methods and materials that are not used in Germany or

Europe will not be subject of the transfer paper. An essential part of the transfer is the

presentation of exposure data on vapors and aerosols out of hot bitumen and the evaluation of

these working place exposures. The German Bitumen Forum holts the largest pool of

exposure data when handling hot bitumen, including data from many European countries.


The analysis and further development of a model for adjusting SCRIM skid

resistance data for temperature and rainfall

ID: 169

Mulry, Brian 1, Brennan, Michael J.

2, Sheahan, Jerome N.

3

1 PMS Pavement Management Services Ltd., Galway, Ireland

2 Academic Consultant, PMS Pavement Management Services Ltd., Galway, Ireland

3 School of Mathematics, Statistics and Applied Mathematics, National University of Ireland,

Galway, Ireland


The skid resistance of a road pavement is not constant and fluctuates throughout the year due

to seasonal variation. The SCRIM machine has been used in Ireland since 1985 to monitor

skid resistance and is operated in accordance with standard HD28 published the National

Roads Authority. A previous study has produced a model to correct for the seasonal effects of

temperature with and without 30-day accumulated rainfall for two different asphalt surfaces, a

surface dressing and hot rolled asphalt, using six years of control circuit data from 2005 to

2010. The findings of this paper will include four more years of skid resistance data collected

from 2011 to 2014 over 5.05 kilometres of the original 7.2 kilometre control circuit. The

additional data was obtained using two SCRIM machines. The overall data set comprises 864

individual SCRIM runs with almost 87,000 50-metre skid resistance data points, and daily

rainfall and temperature records, for the ten year period from 2005 to 2014. The effect of

seasonal variation has typically been understood to change from summer to winter depending

on periods of rainfall or dry conditions. The previous work showed that temperature was a

better indicator than 30-day accumulated rainfall to adjust for seasonal effects. This paper

strives to develop an improved model to identify the seasonal factors that are responsible for

the fluctuation in the sideway-force coefficient (SFC) based on ten years of data from 2005 to

2014 for one SCRIM machine, and also four years of pooled data from 2011 to 2014 for two

SCRIM machines. A new parameter for ‘testing season’ is included in the analysis. The

correlation between the predicted and measured pavement skid resistance is also examined.


Development of a durable third generation Porous Asphalt with a high noise

reduction.

ID: 171

de Bondt, Arian1, Plug, Kees

1, van de Water, Jan

2, The, Peter

3, Voskuilen, Jan

3

1 R&D, Ooms Civiel, Scharwoude, Netherlands

2 Department of Engineering, DIBEC, Nieuwegein, Netherlands

3 Centre for Traffic and Navigation, Rijkswaterstaat,, Delft, Netherlands


The use of Porous Asphalt (PA) has many advantages over standard dense road surfaces. A

disadvantage however is the lower durability of this type of pavement compared to traditional

wearing courses. Due to stricter requirements for noise reduction two-layer porous asphalt

systems were introduced in 2007 in the Netherlands for motorways. Because of the total layer

thickness of 70 mm in combination with a (limited) service life of 8-10 years, the two-layer

Porous Asphalt system is not quite economically to apply within a DBFM contract (such as

A-Lanes A15), because of the 20 years of maintenance. Experiences in Germany with single

layer porous asphalt (OPA), showed that a higher noise reduction than the standard Dutch

Porous Asphalt is possible without loss of durability (with the same end of life criteria). An

intensive research project started to validate and improve the German OPA mixture. Based on

the results it has been found that the used polymer modified bitumen, stone aggregate

selection and filler have a huge influence on the durability. Especially a filler containing the

right proportions of limestone and hydrated lime improves the durability significantly.

Furthermore, selection of a suitable polymer modified binder (PMB) has a strong effect on the

durability. The conducted research project resulted in an approval of the OPA concept by the

national Dutch road authorities (Rijkswaterstaat) as replacement for a standard two layer

Porous Asphalt. The expected service life of the OPA is 12 years (10 years standard service

life and an additional 2 years due to material, production and handling optimization). In 2013,

2014, 2015 and 2016 the OPA is successfully applied (roughly 1.2 million square meters) on

the intensively used Dutch motorway A15 between the junctions Maasvlakte and Vaanplein

(near the harbour of Rotterdam). The overall project has resulted in an optimized supply chain

for the OPA, including the selection of raw materials, the OPA production, transport,

compaction protocol and quality judgement criteria, to get an economically durable Porous

Asphalt with a high noise reduction.


IMPACT: Investigation Machine for Pavement ACoustic durability; Testing

the durability of low noise road surfaces

ID: 230

Angst, Christian Dr.1, Bürgisser, Philip Dr.

1, Beckenbauer, Thomas Dr.

2


2 Müller-BBM Schweiz GmbH, Allschwil, Switzerland


Acoustic durability of asphalt pavements depends mainly on the total number of loading

cycles rather than the age of the road surface. Until now, testing acoustic and mechanical

durability of asphalt pavements is only possible by constructing test-sections and monitoring

the road surface loaded by real traffic. This approach is time-consuming (several years) and

expensive. The aim of the present project is to develop a reliable, fast, and economical

method that allows testing of “low noise road surfaces” regarding durability aspects. The

developed testing equipment is denoted IMPACT and allows simulating traffic, temperature,

load, tread pattern, tyre pressure and wheel spin in the laboratory. In the present project, noise

emission is calculated by means of the computational model SPERoN, based on measurement

of different parameters of the surface. Within only a few weeks of testing, the acquired data

allows assessing the durability of the investigated pavement. Some tests are performed on

different asphalt mixtures. The results of this study will be presented and discussed.


Design of reflective pavements for roads

ID: 233

Huerne ter, Henny L.1, Hetebrij, D.

2, Elfring, J.

3

1 Construction Management & Engineering, University of Twente, Enschede, Netherlands

2 Light Surface Control, Houten, Netherlands

3 Infralinq, KWS Infra, Vianen, Netherlands


Agencies are increasing asking for more reflective pavements in case of non-ordinary

situations. Roads become increasingly visible when using reflective pavements which adds to

traffic safety in dark situations. Reflective pavements can be constructed by using white

chippings in the mixture, by using a blanc bitumen and/or using white pigments. Although the

primary goal is increasing traffic safety, sustainability relating to traffic and transport can also

be improved because public lightning can be reduced in order to obtain equal safety levels or

omitted completely. Reflective pavements also adds to social safety in rural areas where

normally dark areas exists. For instance in tunnels or on cycle paths. It is known that these

type of pavements do help with face recognition at video controlled areas. Within Road

Engineering it is complicated to introduce new asphalt materials. Therefore this branch is

producing and testing laboratory test samples. It takes considerable time before the bitumen

skin has been sufficiently removed in normal traffic conditions for the tarmac to then show its

true reflective values. On the lab samples this traffic processes should be replicated for

creating the correct “test sample” road surface. The paper focusses most importantly on

luminance theory and luminance factors. We also discuss luminance contrast and we focus on

methods to measure luminance quantities from laboratory prepared samples in such a way

that the reflective potential for full-scale situations can be forecast. Further, the paper

discusses the lab testing and lab samples treatment method. In order to create a proper series

of test samples the specific reflective specifications were measured like Rl, Qd, Qo and S1.

During the research different treatment methods of the samples were applied. Finally the

results measured on samples were compared to full-scale constructed road sections. By

analysing the results the team was able to select the most desirable asphalt surface treatment

method for this particular application. The work resulted in the development of four standard

reflective asphalt mixtures for KWS-Infra and a method that can be applied if a reflective

pavement is designed for a specific purpose.


PAHs emissions by Brazilian bitumens

ID: 245

Paniz, Evelyn1, Specht, Luciano Pivoto

1, Pereira, Deividi S.

1, Ferraz, Luis M. R.

2,

Nascimento, Paulo Cícero2, Aragão, Francisco Thiago Sacramento

3

1 Department of Transportation, Universidade Federal de Santa Maria, Santa Maria, RS,

Brazil

2 Department of Chemistry, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil

3 COPPE, Universidade Ferderal do Rio de Janeiro, Rio de Janeiro, Brazil


In the last few years, there has been a great focus with human health and improvement in

workers’ conditions. Within this context, it is necessary to study the impact caused by the

highway construction in people’s life quality. This paper aims to study PAH’s (Polycyclic

Aromatic Hydrocarbons) emission from different bitumens commercialized in Brazil

(conventional, modified by polymer or rubber and natural asphalt). The bitumen’s were

submitted to conventional tests (brazilian specifications) and rheological (SUPERPAVE

classification). The most usual application method is hot mixture. When heated, the asphalt

releases volatile species and solid particles carried by gases which mixture is called bitumen

emissions. Ian this fume there are organic substances (PAH`s), and some of which may be

carcinogenic. Therefore, the fume emitted in the bitumens heating is harmful to health and

should be considered, both from the environmental sustainability and the worker`s health

point of view. PAH`s studies were done alongside with other studies about bitumens where

the bitumen and the emission of some PAH`s were correlated, which will be measured

through an experimental apparatus that generates and collects the bitumen fume. This

equipament is nominated ECD (extraction and collection device). The fumes are collected and

analyzed by LC-MS/MS (liquid chromatography mass spectrometry) to quantify the amount

of emitted PAH`s. From the research, it will be possible to verify if bitumens with different

behaviors at paving have, from the perspective of sustainability, different impacts to the

environment and human health. These emissions, although low, have an impact not well

known on health and environment.


Friction of different surface courses

ID: 256

Patzak, Thomas1, Hase, Manfred

2, Roos, Ralf

3, Wörner, Thomas

1

1 cbm der TU München, München, Germany

2 HNL Ingenieure, Pinneberg, Germany

3 ISE, KIT, Karlsruhe, Germany


Friction is one of the most important facts for drivers, because they think allways to have a

road with good friction values. To get experience with german asphalt surfaces 21 sites from

Bavaria to Schleswig-Holstein examined. Friction after polishing was examined in three

stages on samples drilled out of plates (produced with the roller compactor) and cores from

the sites). The plates were made with asphalt mixtures mixed in the lab and in the asphalt

plant. With this different samples a comparison between laboratory samples and real layed

samples is possible and you can get a decission with which sample a prognosis of the friction

can be made. In addition the texture depth was messured in different stages of polishing. The

tests were made on 16 SMA -, 4 AC - and 1 MA –surface. The statistical calculations show

that there is no difference between the three methods of gaining samples. With this it will be

possible to make a prognosis with asphaltmixtures and moulds produced in the laboratory. It

is shown that the categories given in the EN 13108 don’t fit tot he asphalt surfaces used in

Germany.


The development and use of the Skid Resistance and Smart Ravelling

Interface Testing Device

ID: 290

Khedoe, Radjan1, de Bondt, Arian

1, Villani, Mirella

2, Scarpas, Tom

2

1 Ooms Civiel, Scharwoude, Netherlands

2 Faculty of Civil Engineering & Geosciences, Delft University of Technology, Delft,

Netherlands


Since June 2012, tyre manufacturers have been required to provide data in relation to the

performance of their tyres through testing. The tyre label covers rolling resistance, wet grip or

skid resistance, noise emission. These are important criteria to consider. In the future this kind

of labelling system will be applied on roads. In such a case it is not desirable to build costly

test sites to evaluate these criteria. There is a need of accurate laboratory testing device to

perform such tests. Currently available lab and field friction testing devices do not allow for

the evaluation of the interaction between relative speed, pressure and temperature on friction.

A Skid Resistance & Smart Ravelling Interface Testing Device (SR-ITD®) has been designed

and built for the study of the influence and the interaction of the various phenomena occurring

at the rubber pavement interface. The device enables various combinations of slip velocity

and pressure to be applied with concurrent measurement of temperature in the interface

regions. With this device it is also possible to study the ravelling resistance of a surfacing

material (asphalt, concrete or a surface dressing). The device was developed to study and

evaluate materials in the laboratory on a smaller scale and much faster than in real practice.

The materials to test can be the rubber on the tyres or the surface of the road, asphalt, concrete

or other surface materials. This paper will describe the development and use of the machine

till current date. An optimal tyre can only be developed with a representative road surface also

an optimal road surface can only be developed with a representative tyre. With accurate

testing devices the interaction between tyre and road can be solved.


Safety of road work zones: European and the U.S. perspective

ID: 336

Atahan, Ali Osman1, Buyuk, Murat

1, Malkoc, Gulay

2, Diez, Jose

3

1 Civil Engineering, Istanbul Technical University, Istanbul, Turkey

2 ASMUD, Ankara, Turkey

3 European Union Road Federation, Brussels, Belgium


Highway facilities are built for the purpose of efficiently and economically serving the

transportation needs of the public. During the road construction or maintenance operations the

normal flow of traffic is disrupted by either a change in highway geometry or a temporary

highway closure. These activities present challenges for the safety of workers and the

traveling public. Therefore, work zone on highways have to be designed and managed to

ensure maximum safety and mobility. Unfortunately, the proper treatment for work zone area

in Europe and the US are still overlooked by concerned authorities. Inadequate and improper

selection of traffic control devices can be generally seen in some maintenance sites. Lacking

of consistency and knowledge in designing proper traffic control plan can also be noticed.

The improper use and arrangement of protective control devices within work zone such as

unprotected work space without proper protection devices, loose debris and construction

material on the roadway, and discontinuous barriers to prevent errant vehicles can be widely

observed. This paper presents and compares the key elements for the work zone safety in

Europe and the US. It focuses on particularly functional and physical separation between

workers and traffic, preservation of traffic flows and clarity in the directives and relevance of

the information. Moreover, human targeted solutions, sustainability and safety aspects

obtained from European and US road work zone projects are also addressed.


Health quality assurance approaches for bitumen manufacture and supply

ID: 338

Freeman, James J.1

1 Toxicology and Environmental Sciences, ExxonMobil Biomedical Sciences, Inc.,

Annandale, New Jersey, United States


In 2011, IARC conducted its review of bitumens. IARC published its review in mid-2014 and

highlighted its concern that occupational exposure to bitumen and its emissions includes low

levels of polycyclic aromatic hydrocarbons (PAHs). IARC's rationale included mechanisms of

carcinogenesis involving PAHs. While major reductions in occupational exposure to

bitumen/emissions was recognized by IARC, further effort in this area was encouraged.

Within this context, manufacturers and suppliers of bitumen can take steps to assure that the

content of PAHs in bitumen are minimized. A few conceptual examples follow. Bitumen is

often assigned CAS# 8052-4-42/EINECS 232-490-4. The description for this substance

indicates that the hydrocarbons are “predominantly greater than C25”. Eurobitume, in its

Guidance on Manufacturing Process for Use in REACH Registrations (2008), provides an

interpretation that recombination of streams consistent with this definition can be considered

the substance asphalt. In practice, “predominantly” could be interpreted in different ways. A

consistent interpretation that "predominantly" meets a specific target, e.g., >80%, can be

useful in excluding undesirable lower boiling hydrocarbons, including some PAHs. As further

noted in the Eurobitume Guidance, blending of streams that do not meet this definition could

result in a mixture. Under classification criteria, if such a stream is a Category 1 carcinogen,

e.g., a PAH-rich stream, and at >0.1%, then the mixture would be considered carcinogenic.

While this is broadly understood for product manufacture, it may also have utility in decision

making regarding potential contamination scenarios that could occur either in a plant or

transportation. Lastly, standards can also be established to assure the safety of blend streams.

For example, residual aromatic extract (RAE) substance EC 265-110-5 (CASRN 64742-10-

5), is a potential blend stream for bitumen. CONCAWE established that RAE classification as

a carcinogen needs not apply if it can be shown that the substance has a mutagenicity index

(MI) less than 0.4 as measured by ASTM E 1687-04 or if another predictive test demonstrates

that the substance is not carcinogenic. We demonstrated a relationship (patent pending)

between MI and distillation, such that a distillation measurement (5%GCD) can be used as a

predictive test and quality assurance tool.


PAH`s in bitumen: many paths - one destination

ID: 347

Robertus, Carl1, Thimm, Laima

1, Hossain, Sajjad

1

1 GFT-BIT, BP Europa SE, Gelsenkirchen, Germany


Polycyclic Aromatic Hydrocarbons (PAH), a sub-group of Polycyclic Aromatic Compounds

(PAC), often play a key role in the hazard evaluations of materials and their regulation with

respect to the impact on health and the environment. This is reflected by the large number of

existing inventory lists of PAHs by regulators and advisory bodies. However, in chemically

complex materials or less well defined substances the test method used for determination and

quantification of PAC/PAH may influence the outcome significantly. Recently, PAHs have

played an important role in the outcome of the cancer hazard assessment of occupational

exposure to bitumen and its emissions. Bitumen is a complex substance manufactured from

the distillation of crude oil. It can generally be described as a complex mixture of

hydrocarbons containing a large number of different chemical compounds of relatively high

molecular weight. Under REACH it is a non-hazardous substance and a so called UVCB , a

material “of Unknown, of Variable Composition, or of Biological Origin”. Crude oils contain

low parts of PAH/PAC and as such low (ppm) levels may be present in bitumen. This article

presents results of PAH quantifications carried out in four analytical institutes on a variety of

(intermediate) substances along the bitumen manufacturing process: from crude oil to final

bitumen product. It provides an insight in the development of PAH content during the

manufacturing process of bitumen. The different analytical methods applied in this study are

discussed. Conclusions are drawn focussing on the PAH in the EPA PAH-list. It is shown that

the different (standard) analytical techniques on the complex petroleum substances tested in

this study lead to different results. This in turn stresses the need for standardising test

conditions and/or analytical preparation techniques in order to allow fair comparison of

materials.


Innovative Nano-engineered Asphalt Concrete for Ice and Snow Controls in

Pavement Systems

ID: 388

Ceylan, Halil 1, Arabzadeh, Ali

1, Sassani, Alireza

1, Kim, Sunghwan

1, Gopalakrishnan,

Kasthurirangan 1

1 Civil Engineering, Iowa State University, Ames, Iowa, United States


Each year transportation agencies go through difficulties for ice or snow removal from the

roadways and airport paved surfaces in cold regions. Presence of snow or ice on the paved

areas can cause traffic accidents and financial loss from flight cancellations or delays. For

overcoming the problems associated with winter pavement maintenance, the use of

superhydrophobic (super water-repellent) coating techniques is gaining attention as a smart

and cost-effective alternative to traditional snow and ice removal practices. This study

focused on creating, characterizing, and evaluating innovative superhydrophobic coatings on

asphalt concrete surfaces for ice- and snow-free flexible pavement applications. The Layer by

layer (LBL) method was utilized to create asphalt concrete surface coating with the

polytetrafluoroethylene (PTFE) as a well-known super ice/water-repellent material.

Superhydrophobicity of the coated asphalt concrete surface was characterized in terms of the

water-contact angle. This property was evaluated for different test variables including spray

times and dosage rates of PTFE under a statistical design based experimental test program.

The results of statistical analyses indicate that the spray time and dosage of PTFE

significantly affect the ability of a coated flexible pavement to be

icephobic/superhydrophobic. Based on the results obtained from statistical analysis, asphalt

concrete samples representing the surface texture of flexible pavements were coated using

LBL method. Using a British pendulum tester the performance of coated samples were

evaluated against skid resistance. The measurement results indicate that uses of the LBL

method for spray depositing the PTFE particles is a promising method for achieving

icephobicity, and British pendulum tester can reflect the change effect of the PTFE dosage

over the coated asphalt concrete in terms of skid resistance.


Low Emission2 Asphalt Pavement, LE2AP

ID: 399

Huurman, Marius1, Qui, L

1, Woldekidan, M

1, Demmink, E W

1, Bruin, B. de

1

1 Bam Infra Asfalt, Utrecht, Netherlands


This paper describes progress of the ongoing LE2AP project, acronym for Low Emission2

Asphalt Pavement, where 2 indicates that emission of pollutants during production and noise

during usage are considered. LE2AP concentrates on a novel way of asphalt recycling. Key

issues in the LE2AP approach are that the materials that become available in road

reconstruction are valued. The first step is obtaining these materials by means of dry milling.

Thereafter the reclaimed asphalty is decomposed into its components. As a result of this

reclaimed stone aggregates hardly containing bitumen and a bitumen rich mortar sand - which

is a mixture of bitumen, filler and sand - are obtained. The mortar sand is used as the main

ingredient for the production of a standard mortar. The standard mortar is produced in an

enclosed tank fitted with a stirring device. In this tank the mortar is homogenised and treated

with rejuvenator and soft bitumen. The standard mortar has constant bitumen content and

constant performance characteristic. The standard mortar may be used to produce many of the

porous asphalt mixtures used in the Netherlands today. For the production of denser types of

AC especially sand needs to be added. During mixture production the mortar is foamed and

fed into the mixer where it is mixed with reclaimed stone to obtain a high-grade asphalt

mixture containing a high percentage of reclaimed material produced at low temperature. The

LE2AP project is partially funded via a LIFE+ grant. LE2AP will come to completion in 2016

with the installation of 1 km of pavement surfacing that is produced at ≤80°C, results in ≥7

dB initial noise reduction and that contains ≥80% reclaimed material In this paper the LE2AP

approach is discussed and results obtained so far are shared. The main results that are

discussed are the following. - Decomposition of reclaimed asphalt into its components is

feasible, - Production of a high quality mortar with constant properties is feasible, - The

production of high quality porous asphalt, PA, comprising 93% reclaimed material is feasible,

- LE2AP PA mixtures containing 93% reclaimed material may well outperform their freshly

produced peers, even when produced at reduced temperatures.


5. Binder performance and testing

A two level factorial experimental design for evaluation of viscoelastic

properties of bitumens containing a surfactant warm additive

ID: 13

Hamzah, Meor Othman 1, Golchin, Babak

2, Jamshidi, Ali

3, Valentin, Jan

4

1 School of Civil Engineering, Universiti Sains Malaysia, Nibong Tebal, Malaysia

2 Department of Civil Engineering, Islamic Azad University, Ahar Branch, Ahar, Iran

3 Faculty of Engineering, Hokkaido University, Hokkaido, Japan

4 Department of Road Structures, Faculty of Civil Engineering, Czech Technical University,

Prague, Czech Republic

Topic: 5. Binder performance and testing

In this paper, a two level factorial experimental design was developed to evaluate the effects

of a surfactant warm additive and test temperature on the elastic and viscous properties of

bitumen under unaged, short-term aged and long-term aged conditions. These rheological

properties were measured by the dynamic shear rheometer (DSR) under fixed strains

oscillatory loading at high and intermediate temperatures. The results showed that additive

content and test temperature are significant factors influencing prediction of loss modulus and

storage modulus of selected bitumen at various ageing conditions, but interaction effect of

additive content and temperature is not significant factor on the prediction of loss modulus in

unaged and long-term ageing conditions. Using higher amount of this additive decreases both

loss and storage modulus in various ageing conditions, while increasing the test temperatures

result in lower values for loss and storage modulus.


There is more to say about fatigue and healing of Polymer Modified Asphalt

ID: 25

Vonk, Willem 1, Jellema, Erica

1

1 Research, Kraton Polymers Nederland B.V., Amsterdam, Netherlands


The list of extensive studies on asphalt fatigue and associated healing aspects is long and

impressive. In general there seems to be consensus on a few topics: in nearly all tests carried

out a moderate to significant fatigue resistance improvement is observed when mechanisms

that allow healing are incorporated in the test procedure, while at a similar level of confidence

it has been shown that SBS-modified asphalt shows better fatigue resistance than their

unmodified equivalents. However, where the consensus ends and the confusion starts is when

it comes to healing aspects with Polymer Modified Asphalt. Negative effects on the healing

factors for straight asphalt mixtures and/or binders have been observed with harder bitumen,

lower temperatures and ageing. Hence a correlation with viscosity and thus ease of flow,

wetting and diffusion is plausible and often postulated. So it is counter-intuitive that

numerous researchers have found positive effects on healing with Polymer Modified Asphalt.

Compared to their unmodified base binders they do not have a lower viscosity at the

prevailing temperatures and diffusion is rather hampered than improved by the high molecular

weight species. For some such an outcome is so counter-intuitive that they deny these results

and that may lead to an unnecessary thick pavement design in cases where a lower pavement

thickness could be implemented. For example the Dutch road authorities use a factor of 4 for

unmodified asphalt and use a factor of 1 for PMA, unless proven otherwise. This paper will

provide information on the potential mechanism behind improved healing performance up

and above the improved fatigue characteristics for SBS-modified asphalt.


Evaluation of rheological parameters regarding the resistance to permanent

deformation

ID: 32

Hagner, Tobias1

1 Technischer Kundenservice, TOTAL Bitumen Deutschland GmbH, Brunsbüttel, Germany


The systematic influencing of the performance related properties of binders grows in

importance, taking into consideration the necessity to ensure the durability of increasingly

stressed road pavements. With the growing binder variety, i. e. by modifications with various

polymers, not only the complexity of the specific temperature dependent characteristics of

these binders increases but also the testing methods referring to these characteristics have to

be adapted. Binder tests in the dynamic shear rheometer (DSR) provide the characteristic

parameters complex shear modulus and phase angle. Based on these parameters the

contribution of the binder to the resistance against deformation of the asphalt within the upper

range of the functional temperature can be judged. Whereas the complex shear modulus

describes the stiffness of the binder, the phase angle provides a statement about the shares of

elastic and viscous behaviour. However, it is still not known which of both parameters is

suitable to forecast the effect of the binder in the asphalt. For this purpose a research program

was developed in which four different types of binder, i. e. a polymer modified bitumen, a

paving grade bitumen, a bitumen of modified viscosity and an oxidized bitumen, were

processed in an asphalt concrete and afterwards subject to the Cyclic compression test

according to EN 12697-25. Before the used binders were designed in such a way, that on the

one hand they had the same complex shear modulus and on the other hand the same phase

angle at the testing temperature of 50 °C during the Cyclic compression test. The properties of

the polymer modified bitumen were used as reference. In this paper the characteristics of the

binders and the results of the asphalt tests are presented and at the same time being discussed.


Assessment of asphalt binder viscosities with a new approach

ID: 35

Parhamifar, Ebrahim1, Tyllgren, Per

2

1 Faculty of Engineering, Lund University, Lund, Sweden

2 Swedish Road Center, Malmö, Sweden


A well acquainted method for measuring the viscosity of bitumen, the rotational viscometer,

has undergone major technical improvements in recent years. In several Theses at LTH, the

Faculty of Engineering at Lund University, the use of this technique has been developed step

by step. Along with the WLF (Williams, Landel, Ferry) equation and a correctly digitized

Heukelom’s BTDC (Bitumen Test Data Chart) it has become a useful tool for many purposes.

The utility, reliability and accuracy are demonstrated by testing different types of binders

compared with other methods. A new procedure makes it possible to replace conventional

viscosity methods, even Ring & Ball (Softening Point), with a series of programmed

measurements. The precision is the same as for glass capillaries, even better than for Ring &

Ball, and they seem to coincide well. Special features of modified bitumen are illustrated

graphically and are easily understood, even by an untrained observer. The temperature

dependence of binder viscosities is described with a mathematical relationship based on the

WLF equation. Among many uses the viscosity can be predicted for any temperature and

temperatures may be calculated for any viscosity, especially the Softening Point. Sufficient

space between spindle and container allows testing of asphalt mastics in the same way as

bitumen, which should improve predictions of workability and pavement behavior. In the

daily testing of bitumen, especially at road laboratories, costs are cut and the working

environment is improved, since the use of solvents is reduced and the cleaning up is easy to

do. The measuring process creates no emissions and could even take place on a desk at the

office. It could also be operated from another location. The LTH protocol takes viscosity

measurements into the digital and the mathematical world in tune with modern road design.


Evaluation of the morphological and rheological impacts of cross-linking

agents in polymer modified binders

ID: 42

Ali, Ayman1, Mehta, Yusuf

1, Purdy, Caitlin

1, Nolan, Aaron

1, Villers, Claude

2

1 Civil and Environmental Engineering, Rowan University, Glassboro, United States

2 Civil and Environmental Engineering, Florida Gulf Coast University, Fort Myers, United

States


This study was initiated with the aim of evaluating the relative impact of different cross-

linking agents on the rheological and morphological properties of polymer modified asphalt

binders. To complete this objective, two cross-linking agents (an aromatic oil and silicon

oxide elemental sulfur) were selected for evaluations. The cross-linking agents were then

added to a styrene-butadiene-styrene (SBS) polymer modified binder (virgin PG 70-22) at

different dosages. The selected cross-linking dosages were 2 and 4% by weight of virgin

binder. The SBS, virgin binder, and cross-linking agents were mixed together for 90 minutes

using a high shear mixer. The morphology of the modified binder was then tested using a

florescent microscope and the rheological properties were evaluated using the dynamic shear

rheometer (DSR) to determine the dynamic shear modulus master curves and the multiple

stress creep recovery (MSCR) properties of these binders. The results show that with the

increase in aromatic oil cross-linking agent dosage, there is a reduction in shear modulus

results. In addition, the florescent microscope images show that there seems to be an

improvement in the compatibility between the virgin asphalt and SBS in the presence of the

aromatic oil extracts.


Long-term durability of polymer modified bitumen in bridge deck pavements

ID: 44

Lu, Xiaohu1, Sandman, Bengt

1, Arnerdal, Henrik

1, Odelius, Helene

1

1 Nynas, Nynäshamn, Sweden


Polymer modified bitumen (PMB) has been successfully used for bridge deck application for

a long time. In 1997, a large suspension bridge named the High Coast Bridge was built on the

highway E4 over the Ångermanälven River in Northern Sweden. For this bridge, all asphalt

layers were constructed using polymer modified binders, including asphalt concrete surface

course. In spite of tough climatic condition (a wide temperature span from ca -40°C to 30°C

and large temperature fluctuations) and a high traffic intensity, the asphalt pavement system

on the steel deck has performed excellently. After almost 15 years of service, it was still in a

good condition. To prevent the occurrence of potential stone loss which would subsequently

damage the paint of the steel bridge, the Swedish Transport Administration decided to replace

the top layer in 2012 with a very similar bituminous material. During the re-surfacing

operation, asphalt samples were collected to study the durability of the modified binder.

Extensive chemical and rheological tests were carried out on the recovered binder, as well as

on the original PMB sample. For comparison, laboratory aging tests were also performed. The

results demonstrate that, after a long time period of service, the modified binder is still very

elastic and retains good low temperature and high temperature properties. Furthermore, the

modified binder shows a great resistance to aging. It is evident that the durable PMB has

contributed considerably to the high performance of the bridge asphalt pavement. Long

lasting asphalt pavements with the same PMB are also seen on the Öresund Bridge, a heavily

trafficked bridge between Sweden and Denmark which was inaugurated in 2000. Based on

those good experiences with PMB, polymer modified binders especially designed for bridge

applications have been developed further, and more examples are shown in this paper.


Impact of the bitumen quality on the asphalt mixes performances

ID: 49

Delfosse, Frédéric1, Drouadaine, Ivan

1, Faucon-Dumont, Stéphane

1, Largeaud, Sabine

1,

Eckmann, Bernard2, Planche, Jean Pascal

3, Turner, Fred

3, Glaser, Ron

3

1 Eurovia, Mérignac, France

2 Eurovia, Rueil Malmaison, France

3 Western Research Institute, Wyoming, United States


European refining, French in particular, is currently going through a phase of rationalization

and search for maximum flexibility in crude supplies. For users of bitumen, this creates

concerns about the quality and consistency of products delivered, especially as the European

standard EN 12591 appears to them as insufficient to ensure satisfactory performance of the

finished products, particularly in the case of specialty products such as high modulus asphalt,

polymer modified bitumen, and bitumen emulsions. In this context, the search for correlations

between bitumen properties and the performance of the finished product is more relevant than

ever. The study presented here is focused on asphalt made with pure bitumen. It was based on

a standard design, but with two different types of aggregates. After a preliminary selection, 8

bitumen (20/30, 35/50 and 50/70 pen. grades) were selected. The characterization of asphalt

mixes covers all the usual characteristics (stiffness modulus, resistance to rutting and fatigue,

resistance to thermal cracking, water sensitivity). The characterization of binders, besides

conventional testing, includes the rheological properties (DSR, MSCR, and BBR tests) and

the compositional analysis, particularly infra-red spectroscopy and SARA analysis. These

tests were performed on the original binders, after RTFO, after RFFO + PAV as well as on

the binders recovered from asphalt. This project was conducted as a collaboration between

Eurovia and the Western Research Institute (WRI) which performed the compositional

analysis of binders, including the SAR-AD™ (WRI improved SARA separation technique)

and the chemometrics analysis using their software ExpliFit™.


European round robin tests for the Multiple Stress Creep Recovery Test and

contribution to the development of the European standard test method

ID: 59

De Visscher, Joëlle1, Paez-Dueñas, Antonio

2, Cabanillas, Pilar

3, Carrera, Virginia

4, Cerny,

Radek5, Durand, Graziella

6, Hagner, Tobias

7, Lancaster, Ian

8

1 Bituminous Applications and Chemistry, BRRC (Belgian Road Research Centre), Brussels,

Belgium

2 Technology Prospection, REPSOL, Madrid, Spain

3 Asphalt & Crude Oil Distillation, CEPSA, Madrid, Spain

4 Technology Asphalt, REPSOL, Madrid, Spain

5 Department of Efficient Refining Technologies (UniCRE-EFFRET), Research Institute of

Inorganic Chemistry, Litvínov-Záluží, Czech Republic

6 Campus Scientifique et Technique, COLAS SA, Paris, France

7 Technischer Kundenservice, TOTAL Bitumen Deutschland GmbH, Brunsbüttel, Germany

8 Nynas UK AB, Ellesmere Port, United Kingdom


In 2011, the task group TG1 of CEN TC336/WG1 was assigned the task to produce a

European standard test method for the Multiple Stress Creep Recovery (MSCR) Test. The

MSCR test measures non-recoverable creep compliance and percent recovery using DSR and

is used to evaluate the sensitivity to permanent deformation of bituminous binders. In 2012,

upon completion of the first draft version of the document prEN 16659, TG1 decided to

organize a European round robin test, with 4 different binders. This initiative was taken to

evaluate and improve the test procedure, to allow laboratories to gain experience with the test

method and to determine the precision. Based on the outcome of the statistical analysis and

the feedback from the 25 participants, the draft version was revised and a second round robin

test was conducted in 2014. The specific purposes of this second round robin test were to

expand the precision data to a wider range of binders by testing 7 other binders and to explore

alternative test conditions. This paper reports on the outcome of the round robin exercises and

the findings, conclusions and recommendations of TG1 towards the implementation in the

framework of European binder specifications.


Effects of hot storage on polymer modified binder properties and field

performance

ID: 64

Urquhart, Robert1, Woodall, Elizabeth

1, Malone, Shannon

1, Lourensz, Shannon

1

1 ARRB Group Ltd, Vermont South VIC, Australia


Polymer modified binders (PMBs) are widely used in road construction as they provide

enhanced performance properties (e.g. rutting and cracking resistance) compared with

conventional bitumen. Even though they show enhanced service properties, they may show

degradation or changes in test properties during hot storage. This study investigated the

effects of hot storage (up to 6 days at 180°C) on the test properties and field performance of

PMBs containing low (3.5% by weight) and high (6% by weight) levels of styrene-butadiene-

styrene (SBS) polymer. The chemical changes that occurred during storage were also

monitored using Fourier transform infra-red spectroscopy (FTIR) and gel permeation

chromatography (GPC). The field performance of the PMBs was assessed by conducting

wheel tracking and fatigue tests in a single laboratory dense graded asphalt mix. Both PMBs

showed changes in conventional test properties and chemical composition during storage with

the PMB containing 6% SBS showing the largest changes in penetration at 25°C and

softening point results. Chemical tests indicated that the polymer in both PMBs was

degrading during storage by breaking into smaller fragments. Even though the polymer in the

PMBs was degrading, there was no change in the wheel tracking performance of the 6% SBS

PMB at 60°C when it was stored. The 3.5% SBS PMB showed better wheel tracking

performance after 2 and 4 days storage than prior to it being stored. Both PMBs showed an

improvement in their fatigue performance at 10°C after they were stored. The results obtained

during this study appear to indicate that degradation of the SBS polymer in a PMB during

storage may not necessarily reduce its performance on the road.


Effects of paraffin on low temperature properties of SBS modified binder

ID: 65

Kök, Baha Vural1, Yılmaz, Mehmet

1, Akpolat, Mustafa

1

1 Civil Engineering Department, Firat University, Elazığ, Turkey


The method applied most to improve engineering properties of bituminous hot mixtures

which are used in coating layer is the enhancement of bitumen’s properties with various

additive materials. Polymer based additive materials are generally used for bitumen

modification. Among these additive materials, styrene-butadiene-styrene (SBS) block

copolymers are mostly used. It was determined that SBS increases the resistance of mixtures

against to rutting and fatigue at high temperatures. However it was determined that increased

content of SBS caused both worsening of the low service temperature and also workability of

the mixtures. It is reported that a rubbery network is created which improves elastic response

and enhance low temperature cracking resistance in case the SBS-rich phase forms. It is

known that using paraffin’s property of reducing viscosity and increasing softening point

together with SBS modification which causes increase in viscosity, enhances this combined

binder’s properties of high temperatures and workability; however there exists no study

related to the behavior of this combined binder at low temperatures, in literature. In this study

the effect of SBS and paraffin modification on base bitumen were investigated. Firstly the

bitumen modified individually with SBS and paraffin was evaluated in terms of Bending

Beam Rheometer (BBR) test. Then, the bitumen including both SBS and paraffin in different

contents was tested. Including the three different SBS and paraffin content and also base

bitumen, totally 16 different combination were evaluated. In conclusion, it was determined

that the ratio of stiffness to m-value gives better result in evaluation of low temperature

behavior. At low temperatures, it was determined that stiffness increase with increasing

additive rates; however this increase is much more in paraffin modification, in particular, SBS

addition at low ratio decreases the increase of stiffness caused by paraffin modification.


Comparing field aging to artificial laboratorial aging of bituminous binders

for porous asphalt concrete using black space graph analysis

ID: 70

van Lent, Diederik Quirinus1, Mookhoek, Steven Dirk

1, van Vliet, Dave

1, Giezen, Cecile

1,

Leegwater, Greet Aletta1

1 Netherlands’ Organisation for Applied Scientific Research (TNO), Delft, Netherlands


The majority of the Dutch highway network (approx. 95%) is paved with a wearing course of

Porous Asphalt Concrete (PAC). Aging behaviour of the bituminous binder in the PAC is a

key parameter for the service life of the pavement. In this paper a review is described

concerning the development of field aging and artificial laboratorial aging in terms of the

rheological properties (complex modulus and phase angle) of the bituminous binder. For this

an extensive database with the development of the rheological properties of the bituminous

binder over years from three different pavement trial sections are compared to a large set of

artificial laboratorial aging results found in literature. The results are analysed and compared

by plotting the data together in black space graphs as function of their aging. From these

black space graphs conclusions can be drawn concerning the suitability and predictability of

the artificial laboratorial aging methods for the aging of the bituminous binder in the field. On

basis of the black space graphs it is demonstrated which laboratorial aging technique appears

most representative for simulating ageing in PAC.


Evaluation of bitumens consistence modified by polymers at equipenetrating

temperature

ID: 79

Zolotaryov, Victor1, Galkin, Andrey

1, Pyrig, Yan

1, Kishchynskyi, Sergii

2

1 Department Of Technology Road Building Materials, KHARKOV NATIONAL

AUTOMOBILE ROAD UNIVERSITY, Kharkov, Ukraine

2 Shulgin State Road Research Institute (DNDI) , Kiev, Ukraine


At present the penetration (Р25) and the softening B) remain the main quality characteristic of

both bitumenspoint (ТR B. Theand PMBs. The penetration has more informative valeu

than ТR reason for this is that Р25 is actually a shear strength property of bituminous cements

while dipping the indenter (penetration needle) into them under the effect of stable load.

However, the softening point is valuable only for the bitumens with a low penetration index

but useless in respect of the bitumens which are modified by more than 2,5 – 3,0 % of the

SBS-type polymer. A clear proof of this are the valeus of stability determed during storage,

when a system is formed in the upper part of the tube in which the polymer is the medium and

the phase is the bitumen. Such a system is characterized B.by high penetration and

immensely high ТR According to designers idea the softening point temperature is

informative when the 800×0,1 mm penetration is correspondant. This rule B) can not be

applied to thewhich underlies the ring-and-ball test (R the РМВ. Moreover, long ago I. Ph.

Pfeiffer and P. M. Doormal prefered to use Т800 for specifying the penetration index of

bitumens, which B because of the proximity of thesubsequently transformed into ТR values

of the softening point temperature and Т800 for the “sol-type” bitumen. As for the РМВ the

substitution results in dangerous errors B rut resistance ofwhile forecasting on the basis of

ТR asphalt-concretes. In accordance with W. Heukelom viewing the softening point

temperature in a historic retrospective as the equipenetrating temperature will allow to

enhance the reliability of the РМВ consistence evaluation at high summer temperatures, to

simplify the testing process by means of the traditional and durable penetrometer will be by

using a prolonged needle to 120 mm.


Cohesion of bituminous binders and asphalt concrete strength in shear

ID: 80

Zolotaryov, Victor1, Pyrig, Yan

1, Galkin, Andrey

1, Maliar, Volodymyr

1, Vyrozhemskyj,

Valerii2



2 Shulgin State Road Research Institute (DNDI) , Kiev, Ukraine


Cohesion of bituminous binders is their fundamental characteristic, which allows predicting

the shear strength and rutting resistance of asphalt-concrete. This fact was the base for

inclusion of the cohesion index into EN 14023 in polymer modified bitumens. This standard

offers three characteristics of cohesion measured in dimensions of tensile energy or rupture.

The classical scheme of determining the cohesion of systems similar to bitumen binders is a

one- or two-plane shear; its value is determined by the dimension of strength. The study of

bitumen cohesion and PMB was performed at various shear rate (0,1 – 10 с-1) and at different

temperatures (-30 ... +20 °С). Typical dependences of cohesion are expressed in curves with a

maximum peak at the point of critical temperature, which separates the elastic-viscoplastic

state from the fragile. The peak position of cohesion depends on the shear rate; it is shifted

towards lower temperatures with the increasing of deformation rate, and vice versa. This

temperature is sensitive to the structural type of the bitumens. It is lower for oxidized

bitumens such as "zol-gel" and higher for distillation bitumens such as "zol", both types have

almost similar penetration. The temperature dependences of the asphalt concrete durability are

similar to the analogic dependencies of bituminous binders. Cohesion of oxidized and residual

bitumens with almost similar penetration 75 х 0,1 mm and 79 х 0,1 mm are respectively equal

to 0,12 MPa and 0,11 MPa. Introduction of polymer into the bitumen with a penetration of 96

x 0,1 mm in an amount of 3 %, 6 % and 10 %, results in an increase of cohesion from 0,04

MPa to 0,1 MPa and from 0,1 to 0,14 MPa and from 0,14 to 0,18 MPa respectively, i.e. 2,5,

3,5 and 4,1 times. Between the shear strength of the asphalt concrete and the cohesion of the

binder there is a sufficiently strong correlation: the increase of cohesion by 3,6 times leads to

increase of resistance of the asphalt-concrete to shear under rotation by 2,4 time from 0,14

MPa to 0,33 MPa. This relationship allows predicting the stability of asphalt-concretes against

shear and rutting.


Extraction and recovery of polymer modified bitumen

ID: 82

Hugener, Martin1, Pittet, Michel

2

1 Road engineering/sealing components, Empa, Duebendorf, Switzerland

2 LAVOC, EPFL, Lausanne, Switzerland


The amount of heavy traffic is increasing continuously asking for high performance road

pavements. The higher requirements in terms of stability and fatigue behavior are the main

reason for the elevated use of polymer-modified bitumen (PmB). Despite the fact that PmB

have been known and used for several decades, standardization is still inadequate in some

parts. Only in 2012, the standards for binder extraction and has been adapted to PmB. Still,

binder results obtained by the extraction with different solvents are often questioned. In this

study binder extraction and recovery was investigated in detail for five PmB available on the

Swiss market and four different solvents (toluene, xylene, dichloromethane,

tetrachloroethylene) from the list suggested by the European standard EN 12697-3 for binder

recovery by distillation. In a first step, only the recovery process of dissolved binders was

evaluated. The differences measured between virgin and recovered PmB were remarkably

small for most binder and solvent combinations. In a second step, the extraction process was

verified on a semi-dense asphalt concrete. Again, in most cases the properties of recovered

binders showed little difference concerning penetration and elastic recovery for all four

solvents. Only for some binder/solvent combinations problems were detected, in particular

with dichloromethane. Examination of the residual solvent by gel permeation chromatography

(GPC) showed solvent residues of lower than 0.2% by mass in the case of toluene and slightly

higher residues for xylene and tetrachloroethylene. The study of the micromorphology of

polymers carried out by fluorescent microscopy revealed, with the exception of one binder,

little effect on the distribution and restructuring of the polymers in the bitumen. In conclusion,

it can be confirmed that the standardized extraction and recovery method works well for most

cases with only small deviations from the original values. However, there are binder/solvent

combinations where the extraction is not possible or where large differences between

recovered and virgin binder are encountered for some rheological tests.


Evaluation of rheological effects of waxes on bitumen from different sources

ID: 86

Oner, Julide1, Sengoz, Burak

2, Maidanova, Natalia

3, Topal, Ali

2, Malkoc, Gulay

4

1 Civil Engineering, Dokuz Eylul University, Graduate School of Natural and Applied

Sciences, Engineering Faculty, Izmir, Turkey

2 Civil Engineering, Dokuz Eylul University, Engineering Faculty, Izmir, Turkey

3 Open Joint Stock Company "Asphalt Plant № 1", St. Petersburg, Russian Federation

4 Turkish Asphalt Contractors Association, Ankara, Turkey


Bitumen is adhesive that originates from crude oil and is temperature dependent material

including hydrocarbon molecules. Paraffinic crude oils may provide bitumen of good quality

or yield bitumen which is not suitable for pavement performance. Wax in bitumen has been

referred to as petroleum wax and is obtained from refining of paraffinic crude oils. The effects

of wax on bitumen properties depend on the following factors; the source, chemical

composition and rheology of the bitumen as well as the content, type, composition and

crystallization of the wax. Although high wax contents have been considered as a negative

effect on the quality of the bitumen, there is no common agreement among the scientists

regarding the effect on bitumen rheology and asphalt performance. The scope of this study is

to evaluate the rheological properties of waxy bitumens obtained from different sources.

Following the determination of wax contents by DSC (Differential Scanning Calorimetry) and

EN 12606-1, waxy bitumens properties were evaluated using dynamic shear rheometer (DSR)

and various conventional methods such as softening point, penetration, viscosity, and

ductility. The high temperature performance levels of bitumen were also determined

according to Superpave system by dynamic shear rheometer (DSR) test on samples before

and after aging processes. Besides, bending beam rheometer (BBR) test has been conducted

to investigate the lower critical temperatures of bitumens. Rutting performance of bitumens

has also been evaluated using Zero Shear Viscosity (ZSV) and Multiple Stress Creep

Recovery (MSCR) tests performed in creep mode.


New bitumen performance indicators - A feasibility study

ID: 97

Eckmann, Bernard1, Largeaud, Sabine

2, Van Rooijen, Ronald

3, Planque, Luc

4, Farrar,

Michael5, Planche, Jean-Pascal

5

1 Technical Department, EUROVIA, RUEIL-MALMAISON Cedex, France

2 Research Centre, EUROVIA, MERIGNAC, France

3 GFT Bitumen, BP Europa SE, GELSENKIRCHEN, Germany

4 Bitumen Department, BP France, CERGY-PONTOISE, France

5 Western Research Institute, Laramie, United States


Since the 1999 Eurobitume Workshop, the search and validation of performance related

bituminous binder properties continues to be a key issue for the paving industry in Europe, as

well as in the rest of the world (especially for binders with complex rheological behavior).

Important progress has been made and concepts such as the complex modulus measured with

Dynamic Shear Rheometers (DSR) and low temperature stiffness and relaxation behavior

measured with the Bending Beam Rheometer (BBR) have become familiar, along the lines of

the Superpave system implementation in the US. Measurements in the linear domain of

viscoelasticity have however also shown their limits and a new generation of binder tests,

which try to directly address failure behavior, is now developing. Along with “conventional”

rheology, three such test methods have been contemplated in this paper. In the low

temperature domain, the ABCD (Asphalt Binder Cracking Device) test mimics the TSRST

(Tensile Strength Restrained Specimen Test) performed on bituminous mixes. The LAS

(Linear Amplitude Sweep) test is expected to be related to fatigue whereas the MSCRT

(Multiple Stress Creep & Recovery Test) addresses high temperature performance. To

evaluate the ability of each test method to differentiate between binders, the investigations

have been based on three bitumen of the same penetration grade (70/100) but very different in

chemical structure, varying from a “gel” to a “sol” structure (colloidal index of 0.24 to 0.09).

Full rheology (DSR, BBR), MSCRT, ABCD and LAS tests have been conducted on all three

bitumen, as well as on the corresponding RTFOT hardened and RTFOT+PAV aged binders.

Further developments on the LAS test and its relation to fatigue performance are discussed in

a separate paper by WRI.


CEN TC336/WG2 Round Robin on bituminous emulsions

ID: 100

Eckmann, Bernard1, Le Cunff, France

2, Cresnar, Martina

3, Collins, Steve

4

1 Technical Department, EUROVIA, in the name of TC336/WG2, RUEIL-MALMAISON

Cedex, France

2 Laboratory, CEREMA, ST-BRIEUC, France

3 COLAS GmBH, GRATKORN, Austria

4 AYTON Products, WYMONDHAM, United Kingdom


In Europe, the implementation of CE marking has emphasized the need for simple, robust and

reliable test methods. In the case of bituminous emulsions, these requirements are not always

met and the WG2 working group of the CEN TC336 standardization committee (bituminous

binders) is devoting a large part of his work to improve this situation. One of the on-going

actions aims at replacing the present standard for determination of water content (EN 1428 -

azeotropic distillation) by a much simpler, faster and solvent-free method using a drying

balance. The second action aims at replacing the reference fillers (Sikaisol and Forshammer)

presently used for the determination of breaking behavior (EN 13075-1) by a filler offering

better guarantees of future availability. A third action aims at improving the emulsion

recovery and stabilization procedures described in EN 13074-1&2. After a series of

investigations and preliminary testing among its members, WG2 was able to propose

operating conditions for the drying balance and could identify a new filler (Caolin Q92) for

EN 13075-1. A better insight into the factors affecting the outcome of EN 13074-1&2 could

also be gained and led to new proposals for more strict operating conditions. To validate these

proposals and define precision data (repeatability/reproducibility), WG2 decided then to

launch an extensive Round Robin test program. Conducted on three different emulsions, the

program has gathered 46 laboratories from 14 countries. The paper discusses its outcome

(precision data for the drying balance method, precision data and conversion factors to

Forshammer filler for EN 13075-1, improvements and further progress to be made for EN

13074-1&2). It also underlines the importance (and need) of pre-normative research to

support the work of standardization committees. Acknowledgements are made to CEREMA,

AYTON Products and COLAS Austria for the preparation and dispatching of test samples, to

CEREMA for the statistical analysis and special thanks go to the SFERB emulsion producer’s

associations for their financial support.


GRAPHENE NANO-PLATELET (GNP) REINFORCED ASPHALT

BINDERS AND MIXTURES

ID: 104

Marasteanu, Mihai Octavian1, Le, Jia-Liang

1, Turos, Mugurel Ioan

1

1 Department of Civil, Environmental, and Geo- Engineering, University of Minnesota,

Minneapolis, United States


Researchers at the University of Minnesota have developed a graphene nano-platelets

reinforced asphalt binder that has superior mechanical properties over pavement service

temperatures, compared to existing binder formulations. The costs of these materials are

comparable to polymer modified binders that are considered as best performers in pavement

construction. Examples will be presented to show that for some formulations, asphalt binder

strength at low temperatures doubled compared to the original binder, and fracture energy

increases significantly for asphalt mixtures. It was also found that the addition of graphene

nano-platelets significantly reduces the compaction effort required to prepare asphalt

mixtures. For some formulations, the reduction in compaction effort is more than half of the

original mixtures. Results will be presented for mixture test samples prepared using

traditional mixture preparation, as well as mixture test samples prepared from loose mix. The

effect on rutting behavior is also discussed


New performance indicators for polymer modified binders

ID: 129

Artamendi, Ignacio1, Allen, Bob

1, Sabin, Philip

1, Phillips, Paul

1

1 Research and Development, Aggregate Industries, Hulland Ward, United Kingdom


In Europe, polymer modified bitumens are specified in accordance with EN 14023. These

specifications are based on binder penetration and softening point plus a set of properties

including resistance to hardening, cohesion, Fraass breaking point and elastic recovery. The

European standard also provides a series of classes for each of these properties and enables

the selection of the most suitable class for each polymer modified binder. These properties,

however, provide limited information about their effect on the performance of an asphalt

mixture in the laboratory or during installation, compaction and in-service. In this paper new

binder performance indicators are proposed based on the critical workability temperature of

the binder and a suite of tests on a standardised sand mixture. Critical workability temperature

was determined from binder viscosity data obtained using a rotational viscometer. Tests on a

standardised sand mixture, on the other hand, provided information on the effects of binder

properties on stiffness, oxidative ageing, adhesion, resistance to deformation and low

temperature cracking. Critical workability temperature was then used to classify the polymer

modified binders into five classes, from the most workable to the least workable. Standard

binder properties, critical binder workability temperature and binder’s properties derived from

the sand mixtures were then related to the properties of a dense asphalt concrete mixture.

Asphalt mixture properties evaluated in the laboratory included workability, resistance to

water damage and, deformation, fatigue and fracture resistance. Finally, performance

indicators limits were proposed for each of the binder classes.


A new bituminous binder replacing oxidized bitumen in roofing applications

ID: 134

Mouazen, Mouhamad1, Vincent, Régis

1, Mesnil, Jean-Pierre

2, Lapalu, Laurence

1, Gauthier,

Gilles2

1 Bitumen Department, Total Marketing Services, Solaize, France

2 OMM/BTM, Le Spazio, Total Marketing Services, Paris, France


Thanks to its excellent properties of adhesion, the use of the oxidized bitumen as HAC goes

back up to decades. However, these oxidized bitumen’s stemming from blowing processes

possess a high viscosity leading to an application temperature superior of 210°C. In these

conditions of applications, smokes are generated and can disturb the operator. In the objective

to reduce the application temperature of these HAC, an alternative binder to oxidized bitumen

for bonding applications was developed. This new product possesses similar or superior

performances to those of the oxidized bitumen. It is characterized by a Ring-Ball temperature

close to 100°C and a weak viscosity what allows an important reduction of the application

temperature (from 40 to 90°C). This decrease improves on one hand the comfort of the teams

of application by a remarkable reduction of smokes and on the other hand allows a substantial

energy saving. Besides, pealing experiments showed a bonding property more successful than

that observed with oxidized bitumen. Finally, an excellent creep resistance is demonstrated by

rheological measurements until a temperature of 75°C under load. Consequently, a stability

strengthened by this product in block during its transport and its storage is noted.


Microstructural aging of bitumen

ID: 135

Großegger, Daniel1

1 physical chemistry, institute of material chemistry, Vienna, Austria


The microstructure of bitumen undergoes alteration over time, referred to as ageing. These

structural changes affect the behaviour of bitumen, which can be verified by conventional or

performance orientated testing methods. With different imaging techniques, like confocal

laser scanning microscopy, atomic force microscopy and transmission electron microscopy,

these changes can be made visible. An important issue regards the used methods for acquiring

aged bitumen. Hence field aged bitumen (reclaimed from asphalt) and artificial aged bitumen

(produced by RTFOT and PAV) are investigated. It seems as if a correlation between the size

of microcapsule (often referred to as micelle) and the age of bitumen exists. By separating

bitumen into 4 fractions (saturates, aromatics, resins and asphaltenes) the respective

percentage are determined and an attempt of allocating the fractions to the visualised

microstructure will be done.


LIBS: an innovative technique to improve the knowledge of bitumen elemental

composition : meeting the challenge of metal analysis in an organic matrix

ID: 139

Martin, Hélène1, Durand, Graziella

1, Gueit, Carole

1

1 Colas CST, Magny les Hameaux, France


Main bitumen properties are obtained by standard tests. Analytical techniques can be used to

ascertain their chemical structure but not fully, due to the complexity of bitumens. For several

years, variability in the quality of bitumen has been observed. The conventional laboratory

tests performed on bituminous materials are unable to identify any difference between the

binders in question. An innovative technique rapidly establishes itself to determine the

elemental composition of materials. This method, known as Laser Induced Breakdown

Spectroscopy (LIBS), uses a laser coupled with an optical emission spectrometer. We have

adapted the LIBS protocol to make it suitable for the characterization of bituminous materials.

This method is compatible with the precepts of sustainable development because, amongst

other things, it does not use any solvents and generates no waste. This paper explains the

principle of the LIBS technique, the necessary equipment, the way it is set up and practical

applications in the field of road construction.


Use of maleic anhydride grafted recycled polyethylene treated by irradiation

in bitumen modification

ID: 155

Ahmedzade, Perviz1, Fainleib, Alexander

2, Gunay, Taylan

1, Grigoryeva, Olga

2, Kultayev,

Baurzhan 1, Starostenko, Olga

2, Sakhno, Victor

3

1 Civil Engineering, Ege University, Izmir, Turkey

2 Institute of Macromolecular Chemistry of the National Academy of Sciences of Ukraine

(NASU), Kyiv, Ukraine

3 Institute of Nuclear Research of NASU, Kyiv, Ukraine


Most of the polymers currently used as additive in bitumen are not economically attractive.

Thus, employing recycled materials in flexible highway instead of virgin ones has become a

fundamental case for researchers especially in terms of cost efficiency and environmental

awareness. To date, many studies have been made to investigate using of recycled polymers

in bitumen and generally improved mechanical properties of bitumen were determined. This

paper aims to present the modification of bitumen by maleic anhydride (MAH) grafted

recycled low density polyethylene treated by irradiation (g-LDPEr-g-MA). Maleic anhydride

was dissolved and mixed with recycled polyethylene which was proved by the Fourier

infrared (FT-IR) spectrum. Subsequently, pre-treated LDPEr granules were subjected to

gamma irradiation doze of 10kGy to provide formation of free radicals and some functional

groups which can contribute to creation of strong chemical bonds between polymer modifier

and bitumen. Six different binders (one base and five modified) were prepared to investigate

the effects of g-LDPEr-g-MA modifier on properties of bitumen. The dispersion of g-LDPEr-

g-MA modifier in bitumen was examined by florescent microscope. Conventional tests and

rotational viscosity test was used to determine physical properties of bitumens. Complex

shear modulus (G*) and phase angle (δ) of base and modified bitumens were measured by

means of dynamic shear rheometer (DSR) for different traffic speed and in-service pavement

temperature. Tests results reveal that a gradually increment in g-LDPEr-g-MA modification

leads to a decrease in penetration and an increase in softening point. According to DSR test

results, g-LDPEr-g-MA modifier provides an increased rutting parameter. Thus, flexible

pavement could become more resistant against permeant deformations by g-LDPEr-g-MA

modification.


Study of the low temperature characteristics of binders and the asphalt

mixtures produced with them

ID: 158

Pangarova, Dafinka1, Nikolov, Alexander

2

1 Chemistry, Central institute of road technologies national and European norms and

standards, Sofia, Bulgaria

2 Research and development, Patpribor OOD, Sofia, Bulgaria


The asphalt pavements performance at low service temperatures is highly dependent on

binders’ behavior at low temperatures. At present it is only recommended in the specification

for polymer modified binders to be tested the performance characteristic – stiffness at -16oC

with BBR according to EN 14771. For the rest of the binders it is only required to be tested

the Fraas breaking point according to EN 12593. There is no specification limiting the

threshold stiffness value. Binders, modified with organic, inorganic polymers and paraffin

waxes have been tested. The rheological properties were examined at different service

temperature intervals, where the low temperature intervals were tested according to Fraas

breaking point and BBR test methods. Both short term and long term aging have been carried

out according to EN 12607-1 and EN 14771 respectively. For asphalt mixtures prepared with

the same binders the indirect tensile strength has been tested according to EN 12697-23, but at

low temperature. The aim of the study is to be found correlations between the low

temperature properties of the binders and the asphalt mixtures prepared with them.


Lignin as a green alternative for bitumen

ID: 159

van Vliet, Dave1, Slaghek, Ted

1, Giezen, Cecile

1, Haaksman, Ingrid

1

1 TNO, Netherlands Organization for Applied Scientific Research, Delft, Netherlands


In 2014, the European bitumen consumption was 11.3 Mt. The paving grade bitumen

comprise the greater part of the bitumen consumption (83%). Generally, traditional hot mix

asphalt emits large quantities of CO2, CH4 and N2O. This material is part of the high carbon

emissions disaster area of the high-way industry, which is unfavorable to the development of

a low-carbon economy. Another challenge for the bitumen industry is that the petrochemical

industry is becoming more and more efficient in breaking down higher chain hydrocarbons to

lower chain hydrocarbons with higher added value than bitumen. This has an effect on the

availability of bitumen. The asphalt market is looking for alternatives with higher

sustainability in terms of CO2 emission. The usage of alternative sustainable binders, which

can (partly) replace the bitumen, contributes to reduce CO2-emissions and at the same time

broadens the availability of binders. The paper will describe the use of lignin as a “partial”

substitute for bitumen. The alternative polymer that has been be researched as a “partly”

alternative for bitumen originates from nature and is called lignin. Lignin is one of the most

abundant natural polymers (next to cellulose and hemi cellulose) present in plant material.

The chemical structure known today does reflect the structure for bitumen and therefore it

could be used as an alternative for bitumen in applications like roofing or asphalt. The paper

will describe the proof of concept in using lignin, as replacement or partial replacement of

bitumen without losing its functionality. Several types of lignin and bitumen blends have been

researched. Not only native lignins but also modified lignins have been researched. These

modifications were performed to meet original binder (bitumen) properties or to improve

binder properties. For the evaluation of the lignin-bitumen blends properties (chemical and

mechanical), techniques such as DSR have been used. In conclusion the paper will describe

the results of this evaluation.


Determination of the viscosity of bitumen or mortar measured by the tensile

retardation test (ReVis)

ID: 164

Schellenberg, Kurt1, Eulitz, Hans-Jörg

2, Paschke, Katrin

3

1 Institut für Materialprüfung Dr. Schellenberg Rottweil GmbH, Rottweil, Germany

2 Ingenieurbüro Dr. Eulitz, Drage, Germany

3 Technische Universität Dresden, Dresden, Germany


Prismatic samples with suitably large dimensions enable tensile retardation tests to

measurement the viscosity of bituminous binders as well as the viscosity of mixtures of binder

and filler. During the test the sample is put in horizontal positon lying nearly frictionless. In

this position the sample is subjected to spontaneous tensile stress. The tensile stress is

generated by a unit of stepping motor with transmission. The elongation of the sample is

measured by displacement sensors. As the test result the tensile viscosity can be determined.

The Diagrams of the logarithmic of viscosity values versus the test temperature indicate a

strict linear slope. Noteworthy is, that the viscosity values correlate with the Ring and Ball

temperature of pure bitumen grades but not in case of polymer modified bitumen. For pure

bitumen, polymer modified bitumen and also for mixtures of bitumen and filler, the viscosity

values λZ measured by the tensile retardation test can be describes exactly with the equation

log (λZ) = a+b*t. Therefore in case of routine purposes the test can be carried out at only one

temperature yielding a characteristic viscosity value. This Value that can be used also as an

input for structural design. The viscosity of bituminous mortar measured with the tensile

retardation test (called ReVis) provides valuable information on asphalt mix regarding with

regard to its resistance to permanent deformation at higher in-service temperatures.


Bitumen-in-water emulsion: Destabilization by electrolyte solutions and

rheological evaluation

ID: 168

Boucard, Laure1, Schmitt, Véronique


1, Farcas, Fabienne

3, Gaudefroy,

Vincent1

1 IFSTTAR, Bouguenais, France

2 CRPP-CNRS, Pessac, France

3 IFSTTAR, Marne la Vallée, France


The breaking process of the bitumen emulsion is initiated when put into contact with

aggregates during the mixing step. It is due to interactions between the binder and the

aggregates and also water loss (evaporation and gravity flow). Some mechanisms are

supposed to play a role in the breaking process which highly rules the coating quality of the

aggregates by the bitumen binder, the implementation step of the mixture on the pavement

and the final mechanical properties of the mixture. However the bitumen emulsion breaking

process is not fully understood. It remains difficult to know which parameters have a

preponderant role on emulsion breaking and how the kinetics of the different involved

phenomena impact the global destabilization. The first part of the presented paper aims to

determine the influence of electrolyte solutions, used as emulsion destabilizing agents to

simulate ionic species release in the aqueous phase of the emulsion by the aggregates, on

concentrated oil-in-water bitumen emulsion stability. Secondly, the evolution of rheological

properties of the emulsion during destabilization process, which have been put in evidence in

the first part, will be presented and discussed The emulsion destabilization, which included a

gelation process, has been evaluated by macroscopic and microscopic observations, as well as

size distribution and rheological measurements. An interpretation of the destabilization

processes will be drawn using rheology, the emulsion formulation and the electrolyte

solutions.


Quality assessment of polymer modified bitumen - performance related test

methods and field performance

ID: 170

Jörgensen, Torbjörn1, Hovin, Wenche

2, Saba, Rabbira Garba

2

1 Road Technology Section, Norwegian Public Roads Administration, Oslo, Norway



As a part of a research and development project conducted by the Norwegian Public Roads

Administration, an investigation was conducted on the quality of Polymer Modified Bitumen

(PMBs). Norwegian PMB grades are typically soft penetration grades with a high content of

elastomeric polymer. Both softening point and elastic recovery are high, keeping good low

temperature properties. A follow-up on PMB samples taken from road sections with PMB

modified asphalt concrete included testing of RTFO-aged PMBs. Traditional test methods

were used together with Dynamic Shear Rheometer testing: involving Complex Modulus and

Multiple Stress Creep Recovery Test (MSCRT). A special effort was made to gain insight

into the MSCRT, including how to do the testing and the criteria to be used in future

requirements. The condition of the Norwegian Public Road net is measured annually with a

mobile laser profile scanner. Rutting data from selected sites were linked to PMB test data

from corresponding control samples. Data from road sections and laboratory tests were

compared to find any correlation between field and laboratory data.


Designation of the viscosity of binder with the tension retardation test

ID: 174

Bommert, Franz1

1 Highway construction, Federal Highway Research Institute (BASt), Bergisch Gladbach,

Germany


The performance of asphalt by low temperatures is largely determined by the viscosity of the

binder respectively the mortar of the asphalt. The traditional test methods for binder (e.g. ball-

draw viscosimeter) are limited to temperatures above the service range of temperature for an

asphalt construction. The Dynamic Shear Rheometer (DSR) is limited to temperatures above

30°C whereas the Bending Beam Rheometer (BBR) is limited to temperatures below -10°C

and not applicable to mortar. Especially the gap in the temperature of these test methods is

very important to characterize the viscosity behavior of binder and mortar over the whole

range of the service temperatures, which represent the typical environmental conditions of

over the seasons, for an asphalt construction. Tension retardation experiments seem to be very

useful to bridge the gap. They address the low temperature behavior of binder and mortar.

With this test method the flow characteristics of binder (pen grade and any modification) and

any kind of mortar in the service temperature range, in particular at low temperatures of -25°C

can be determined with a high precision, and assessed, via the physically interpretable

material characteristics quantity of tension viscosity. Furthermore the present findings

indicate the potential of extrapolation the results of the Tension retardation for a prediction of

the rutting resistance of asphalt mixtures. As part of several research Projects, BASt (Federal

Highway Research Institute) investigated the effects of different modifications of the binder

to low temperature behavior of the binder by the tension retardation test. This paper is

intended to provide a more detailed description of the test method Tension Retardation,

selected results and related findings.


The effect of binder composition and properties on the water sensitivity of

asphalt mixtures

ID: 187

Lancaster, Ian Michael1, Lancaster, Ian Martin

1

1 Nynas UK AB, Ellesmere Port, United Kingdom


Resistance of asphalt to the effects of water is of fundamental importance to the long term

durability of the pavement structure. This paper compares two standard methods frequently

used in the UK to assess the water sensitivity with real-time, long-term field exposure. Five

binders, including paving grade and polymer-modified binders of similar nominal penetration

were used to produce AC10-type asphalt with two different aggregate sources. The Indirect

Tensile Stiffness Modulus (ITSM) of the field-exposed asphalt samples was evaluated at

regular intervals over a two year period and compared to those obtained under the standard

methods. It was found that there was little correlation in the results obtained using the

standard methods to the those from the field aged samples.


Nonlinear oscillatory shear tests applied to bitumen: analysis and application

of large amplitude oscillatory shear (LAOS)

ID: 189

Cookman, Alec Otto1, Farrar, Michael J.

1, Planche, Jean-Pascal

1

1 Western Research Institute, Laramie, WY, United States


The characterization of bitumen binder fatigue properties has been a difficult challenge since

the introduction of the Superpave system in the early 90’s. Originally, rheological testing was

performed in the linear viscoelastic region, but was found not necessarily adequate to show

the impact of modified binders. Recently, researchers at the University of Madison-Wisconsin

considered nonlinear region conditions to develop the Linear Amplitude Sweep (LAS) test.

They showed the potential of such conditions to differentiate binders with respect to

modification. In this study we have tried to go one step further by characterizing the

rheological behavior of bitumen in the nonlinear viscoleastic region by an oscillatory

deformation protocol known as large amplitude oscillatory shear (LAOS). To date, there has

been little application of LAOS to characterize the nonlinear viscoelasticity of unmodified

and modified bitumen. The common practice has been to apply the “viscoelastic moduli”

corresponding to the first harmonic Fourier coefficients G1' (ω), G1'' (ω). However, in many

cases that can be misleading in describing the nonlinear phenomena. The focus of this paper is

to demonstrate the application of LAOS to the LAS test and point out some limitations in the

way the LAS test currently analyzes oscillatory shear in the nonlinear regime using just the

first harmonic. The framework of our LAOS analysis is in terms Lissajous curves and Fourier

series and transforms.


Identification of structural changes in bitumen due to aging and fatigue

ID: 196

Cannone Falchetto, Augusto1, Alisov, Alexander

1, Goeke, Matthias

1, Wistuba, Michael P.

1

1 Department of Civil Engineering, Technische Universität Braunschweig, Braunschweig,

Germany


Bitumen is one of the basic constituents, together with aggregates, which is used to prepare

asphalt mixtures for pavement applications. This material is temperature susceptible and

subject to oxidative ageing. Bitumen is commonly modelled as a colloid with asphaltenes as

the dispersed phase and maltenes as the continuous phase. Additional phenomena such as

stress and fatigue effects can influence the structure of bitumen and, ultimately, affect

pavement performance and durability. In the present research, the effect of ageing and fatigue

stresses on the microstructure and on the molecular components of bitumen is investigated. A

plain bitumen 50/70 and a polymer modified bitumen 25/55-55 were evaluated in two

different ageing conditions: virgin and aged. The influence of fatigue stress was taken into

account by performing shear tests with the Dynamic Shear Rheometer. Thin-layer

chromatography, infrared spectroscopy and atomic force microscopy (AFM) were then used

to evaluate the structural changes in the materials associated to ageing and fatigue. The results

of the chromatographic analysis suggest that the structural changes are proportional to the

variation in the bitumen fractions (resins, aromatics, saturated hydrocarbons). The infrared

spectroscopic analysis was proven to be suitable for detecting structural changes of virgin,

aged and fatigued bitumen. This was confirmed by variations in intensity of transmission

spectra due to increased or decreased molecular vibrations of functional groups for specific

wave numbers. AFM microscopic analysis showed significant changes in the surface bee-

structures between virgin and aged bitumen. The selected experimental methods were able to

distinguish microstructural and molecular variations due to ageing and fatigue providing

evidence that the mechanical response of bitumen is linked to the physical and chemical

properties which are critical for achieving durable and consistent asphalt pavement

performance.


Cracking of asphalt pavements and the development of specifications with

rheological measurements

ID: 215

Rowe, Geoffrey M.1, Sharrock, Mark J.

1

1 Abatech, Blooming Glen, United States


The use of linear visco-elastic analysis methods for the characterization of asphalt binders has

gained popularity since the wide introduction of rheometers in the early/mid 1990s. The use

of the G*.sin(delta) parameter for fatigue cracking has been suggested as lacking the

validation with field performance. However, this parameter at the intermediate temperature

results in a required rheological index for the asphalt binder. The rheological index can be

considered to be related to the requirement for grading at an intermediate temperature and can

be expressed as a function of delta(t), the difference between the low temperature grade

specified and the temperature used for the intermediate grade requirement. The R-value as

developed by Christensen and Anderson is related to the relaxation spectrum and this is

related to many of the parameters that correlate to cracking. For example French workers have

suggested that the standard deviation of the relaxation spectra was an important consideration.

Other concepts such as the Glover-Rowe parameter, visco-elastic transition temperature

(VET) and/or the use of phase angle to understand fatigue can all be related to this R-value.

This paper discusses the development of the specification around the concept of R-value and

how this is controlled within the current specifications and the interrelationships between this

parameter and various cracking studies.


Vialit Cohesion and Cracking Performance

ID: 216

Rowe, Geoffrey M.1

1 Abatech, Blooming Glen, United States


The Vialit Cohesion Pendulum has been used for many years in Europe as a tool for assessing

modified binders with a particular emphasis on chip seals/surfacing dressing applications. The

cohesion measured in this device has been considered as an indicator of quality of the

bitumen and subsequent polymer formulation. This test demonstrates a transition between

brittle and ductile failure Z(flow) of binder systems. Data will be presented from a series of

tests conducted on SHRP core asphalts and these will be compared to fracture tests and

master curves developed with the same binders. A discussion will follow on how the fracture

of asphalt binder and mix is both rate and temperature dependent and that this parameter

always needs that consideration to truly evaluate the meaning of test data. A test of this

nature, while founded partly on an empirical data base of use can be better explained and

understood with the consideration of speed of loading and temperature effects this allowing

translation of fracture temperatures at one condition to those at another.


Effect of polyphosphoric acid on aging kinetics of bituminous binders

ID: 218

Shulga, Olga1, Maldonado, Rene

1

1 ICL Performance Products, St.Louis, United States


Polyphosphoric acid (PPA) is widely used asphalt modifier to improve the properties of neat

asphalt binders when added at low concentrations. Since PPA acts to stiffen the binder, there

has been a concern that PPA also accelerates oxidative aging of asphalt. The purpose of this

study was to evaluate the effect of PPA on the aging kinetics of asphalt binder. We used

extended PAV aging at various times followed by determination of carbonyl contents and PG

grade after each aging period. PAV material containing the binder modified with 1% PPA

was investigated by DSR and BBR and showed that such binder has wider Effective

Temperature Range, compared to control without PPA. The binder with 1% PPA exhibits

improved high temperature stiffness. After 60 hours of PAV aging, the low temperature

properties of the PPA modified binder are comparable to those of the original, unaged binder.

The control binder without PPA exhibited expected changes due to oxidative aging,

proportionate to PAV exposure time. The rate of carbonyl formation was approximately 12%

slower for PPA-containing binder than the control without PPA. These improvements

strongly suggest that the use of PPA improves a binder’s resistance to oxidative aging.

Bitumen recovered from compacted mixes containing 35% of recycled asphalt pavement

(RAP) and PPA-modified binder also show lower stiffness for PPA-containing binders. This

suggests that PPA-modified binders may provide anti-aging benefit and reduce the need for

rejuvenating agent in the RAP mixes.


Rheological behavior of vegetable oil-modified asphaltite binders and mixes

ID: 222

Somé, Ciryle1, Pavoine, Alexandre


2, Andrieux, Laura

1, DeMarco,

Laurent1, Philippe, Da Silva

1, Stephan, Benard

1

1 Laboratoire EcoMatériaux (LEM), CEREMA/Dter IdF, Sourdun, France

2 IFSTTAR, Nantes, France


This paper focuses on the development of a viscoelastic bituminous binder by blending hard

natural bitumen (asphaltite), waste vegetable oil and a small amount of hard petroleum

bitumen. The optimization of the composition of this mixture allows obtaining binder with

similar needle penetration as classical paving grade bitumen. The obtained product is

expected to be an alternative to the consumption of the classical petroleum bitumen and a new

way to recycle waste vegetable oils. Two waste vegetable oils (rapeseed and sunflower) have

been used for this issue. The appropriate composition of the blends has been firstly

determined based on the conventional penetration and softening point tests. The volatility of

the constituents of the binders has been measured thanks to a thermo-gravimetric analyses

(TGA). The linear viscoelastic properties of the binders and the corresponding asphalt

concretes have been also measured. In addition, theirs performances regarding the resistance

to the permanent deformation and the water sensitivity have been evaluated. It has been found

that the produced binders and the corresponding mixes have lower stiffness modulus than the

classical 35/50 paving grade bitumen. The rutting depths, the stripping resistances as well as

the stiffness modulus obtained with the new binders comply with the actual standard 13108-1,

except the stiffness modulus obtained with the waste rapeseed oil.


Rheological evaluation of bitumen modified by various biochars

ID: 232

Çeloğlu, Muhammed Ertuğrul1, Yılmaz, Mehmet

1, Kök, Baha Vural

1, Yalçın, Erkut

1

1 Civil Engineering, Firat University, Elazığ, Turkey


Bituminous binders as one of the two main elements which constitute flexible pavement

friction layers, are obtained through refining of petroleum. Highway industry is faced with the

problem of gradually increasing prices and decreasing bituminous binders which are used in

flexible pavement construction. Depending on the economic growth and population increase;

new highways constructed due to constantly increasing transportation demand and

maintenance of current roads result in increase of the amount of required bituminous binders.

Economic and environmental problems caused by using fossil-based materials revealed the

need of miscellaneous alternative materials to be considered in terms of sustainability in

highway industry. Biomass is one of the greatest and renewable energy resources of the

world. After applying pyrolysis to biomass, bio-chars has the potential of being used with

conventional petroleum products. Vegetable based materials having the structure of

hydrocarbon and renewability in short time exposed that these materials can be used as

pavement materials. Liquid product obtained after pyrolysis is called as bio-oil, solid product

is called as biochar. In this study, usability of biochars obtained through pyrolysis of walnut

crust and apricot seed shell whose economic value is low, as additive for bituminous binders

were investigated in order to improve the performance of highway pavements. Modified

bitumen samples were produced by mixing base bitumen with biochars at three different

additive contents. The conventional properties of the modified binders were evaluated in

terms of their properties using penetration, softening point and dynamic viscosity tests. The

fundamental viscoelastic properties of the modified binders were determined using dynamic

(oscillatory) mechanical analysis and were presented in the form of temperature- and

frequency-dependent rheological parameters. It was determined by the results obtained from

the conventional tests that the softening point and the viscosity increased and the penetration

and the thermal sensitivity decreased with increased biochar contents. Dynamic shear

rheometer test results indicated that the complex modulus values of modified binders

increased and phase angle values decreased with biochar usage. Test results are an indication

that the biochars have promising potential to reduce the permanent deformation or rutting of

asphalt pavements.


Effects of nanoclay modification on the rheological properties of bituminous

binders

ID: 235

Yalçın, Erkut1, Yılmaz, Mehmet

1, Kök, Baha Vural

1, Çeloğlu, Muhammed Ertuğrul

1

1 Civil Engineering, Firat University, Elazığ, Turkey


The rheological behavior of bitumen is very complex phenomenon varying from purely

viscous to elastic depending on loading time and temperature. As a visco-elastic material,

bitumen plays a prominent role in determining many aspects of road performance. Numerous

investigations have been carried out on incorporating modified bitumens to improve the

performance of bituminous composites. This paper presents a laboratory-scale evaluation of

the conventional and the fundamental rheological characteristics of modified binders

including nanoclay contains 35-45 wt. % dimethyl dialkyl (C14-C18) amine (DANC) and

montmorillonite. Modified bitumen samples were produced by mixing base bitumen with

DANC and montmorillonite at three different additive contents. The conventional properties

of the modified binders were evaluated in terms of their properties using penetration,

softening point and dynamic viscosity tests. The fundamental viscoelastic properties of the

modified binders were determined using dynamic (oscillatory) mechanical analysis and were

presented in the form of temperature- and frequency-dependent rheological parameters. It was

determined by the results obtained from the conventional tests that the softening point and the

viscosity increased and the penetration and the thermal sensitivity decreased with increased

DANC. Dynamic shear rheometer test results indicated that the temperature and the frequency

had a significant effect on the complex modulus of DANC and montmorillonite modified

binders. The research results are an indication that the DANC has promising potential to

reduce the permanent deformation or rutting of asphalt pavements. Investigation of the types

of different additives yielded that the most effective additive was DANC in all experiments.


Change in Bitumen Quality during the working stations

ID: 255

Wörner, Thomas1, Hase, Manfred

2, Roos, Ralf

3

1 cbm der TU München, München, Germany

2 HNL Ingenieurgesellschaft, Pinneberg, Germany

3 ISE, KIT, Karlsruhe, Germany


The change of bitumen quality was investigated for 21 sites and three layers. Therefore

samples were examined at the stage of delivery, after mixing in the lab, after production in the

asphalt plant and after laying. The bitumen are discribed with the conventionel test methods

(Softening Point, Penetration), with tests in the Dynamic Shear Rheometer (temperature

sweep for phase angle and stiffness, Multiple Stress Creep an Recovery Test), with Bending

Beam Rheometer and Force Ductility. The study included conventionel bitumen (EN 12591)

and modified bitumen (PmB based on EN 14023) and with waxes modified bitumen. In some

asphalt mixtures reclaimed asphalt was used. The results show the influence of the reclaimed

asphalt on the bitumen quality and they show too that the different asphalts (AC, SMA, MA)

stress the bitumen not constant. The bitumen used in asphalt for binder-courses was stressed

much more than bitumen in other asphalt mixtures. The effect of higher modified bitumen

seams to be adapted to normal modified bitumen after asphalt production and laying.


Assessing bitumen in the whole service-temperature-range with the dynamic

shear rheometer

ID: 259

Radenberg, Martin1, Gehrke, Michael

1



During a research project in the years 2012 to 2014, 90 bitumens of different grades from

eight different refineries were analyzed thoroughly. The results provide a detailed and

extensive overview about the rheological properties and chem-ical compositions of the

bitumens used in road construction in Germany. The results, measured with the Dynamic

Shear Rheometer (DSR) at cold temperatures, correspond well with the stiff-ness and the

relaxation-properties, measured with the Bending Beam Rheometer. The stiffness at 25 °C

corresponds well with the needle penetration at the same temperature. The improvements of

the DSR-analysis at this temperature are a better differentiation of harder bitumens and the

additional information, given by the phase angle. The properties at high service temperatures

could also be analyzed more precisely and more performance related with the DSR. Un-

modified bitumens show a precise correlation between the stiffness and the softening point

ring and ball. Due to the fact that the determination of the softening point of modified

bitumens often causes problems, an equiviscosity tem-perature for the shear modulus of 15

kPa is a suitable substitute for the softening point ring and ball. For the very rea-son that the

viscosity at high temperatures is a suitable criterion for the asphalt’s production, processing

and compac-tion, the DSR gives an analysis of the bitumen’s whole service-temperature-

range. The results of the research project show that all currently used test methods can be

replaced equivalently by the DSR. Furthermore, the DSR provides characteristic values for a

more precise bitumen analysis, particularly for modified bitumens.


Assessment of performance specification tests for rheologically simple

bitumens

ID: 269

Kriz, Pavel1, Grant, Daniel

1, Boussad, Nadjib

2, Gausson, Danielle

2, Cointe, Frederique

3,

Toulemonde, Charlotte3, Shirts, Ralph

4

1 Research Department, Imperial Oil Limited, Sarnia, ON, Canada

2 European Technology Centre, Esso S.A.F., Notre Dame de Gravenchon, France

3 Esso S.A.F., Courbevoie, France

4 ExxonMobil Corp., Spring, TX, United States


The current edition of the European standard for specifying paving grade bitumens (EN

12591) is based on empirical test methods, such as penetration and softening point. Since the

USA and Canada successfully adopted the rheology based performance specification system,

Superpave, the discussion whether to introduce rheology tests and develop performance

specification has moved to Europe. Recently, a Comité Européen de Normalisation (CEN)

proposal to start collecting rheology data for bitumens has been drafted. For low temperature

performance assessment, an approach nearly identical to Superpave was selected; low

temperature testing in a Bending Beam Rheometer (BBR) performed on long term aged

bitumen. For high temperature performance assessment Superpave equiviscous testing was

not adopted. An isothermal dynamic shear rheometer tests at 15, 40 or 60 °C were selected to

be performed on short term aged bitumen instead. This paper offers a comparison between

empirical and rheology test methods. It highlights the advantages and disadvantages of each

testing system. It explains the philosophy in Superpave specification and the process by which

the rheology test results are related to bitumen performance in asphalt. Current CEN proposal

for rheology data collection is reviewed and suggestions to development of a performance

based specification system are provided.


Effect of ageing on the low temperature properties of bitumen

ID: 273

Ravnikar Turk, Mojca1, Tušar, Marjan

2, 1

1 Slovenian National Building and Civil Engineering Institute, Ljubljana, Slovenia



Properties of aged binder are believed to be relevant for low temperature cracking of asphalt.

The properties of bitumen at low temperatures have been determined for many years with

Fraass fracture temperatures of fresh bitumen. Since Fraass braking point test has several

shortcomings, additional parameters like stiffness and creep rate were introduced with

Bending Beam Rheometer (BBR) method. The BBR method has been standardized (EN

14771) but it is still not widely used in middle Europe, mostly because it is intended for the

investigation of aged instead of fresh bitumen, and secondly, the limit values for evaluation of

the quality of bitumen are still not set. In our study six samples of original bitumen B70/100

were extensively tested. The purpose of the study was to determine the impact of aging on the

most commonly used types of paving grade bitumen B70/100 in Slovenia and to propose

criteria for bitumen quality based on evaluation of obtained test results. On original bitumen

the usual scope of bitumen tests (R&B, Penetration, Fraass) was performed and additionally

BBR test. These bitumen were also tested after short term aging (RTFOT method) and long

term aging (PAV method). In this study, the sensitivity to aging and temperature, as well as

low temperature behaviour of these bitumen was evaluated on the basis of the results of the

tests. Additionally we determined some correlations between results of BBR test and

conventional bitumen tests. Correlations between all test results were visualized with

principal component analyses (PCA) method and then the most adequate model of BBR

results in dependency to all other test results was determined with Multivariate linear

regression.


Effects of filler/bitumen ratio and bitumen grade on rutting and fatigue

characteristics of bituminous mastics

ID: 298

Vale, Aline Colares do1, Faxina, Adalberto Leandro

1, Grecco, Franciele Luisa Gutierrez

1

1 Transportation Engineering, University of Sao Paulo, Brazil, Sao Carlos, Brazil


Bituminous mastics are a blend of bitumen and the finest mineral particles which have the

role of filling the voids created by the coarse mineral aggregates. The rheological properties

of the mastic phase have a determinant effect on the mechanical behavior of the whole asphalt

and can be evaluated in the light of tests recently developed for pure and modified bitumens.

The objective of this research is to evaluate the effects of different filler/bitumen ratios and

two bitumens grades (50/70 and 30/45) on rheological properties of bituminous mastics

associated with permanent deformation and fatigue cracking. The original samples were

subjected to short- and long-term ageing according to standard procedures using a rolling thin

film oven and a pressure ageing vessel. The short-term aged samples were submitted to the

MSCR test and the long-term aged samples were submitted to the LAS test. The MSCR test

was performed at 52, 58, 64, 70 and 76°C in order to cover a wide range of temperatures

where permanent deformation can occur. The LAS test was run at 25°C, which is a typical

temperature where fatigue cracking appears in the asphalt. The overall conclusions are: (i) the

filler/bitumen ratio are responsible for an expressive increase in the resistance of the asphalt

to the accumulation of plastic deformations and these positive effects are more expressive

when a harder bitumen is used; (ii) in the light of the af parameter, obtained from the fracture

mechanics, the harder the bitumen and the higher the f/b ratio, the higher the tolerance to

fatigue damage of the mastics, but, on the other hand, the fatigue life curves, obtained from

the continuum mechanics, indicated the opposite, i.e., the harder the bitumen and the higher

the f/b ratio, the lower the fatigue life of the mastics. The analysis based on the fatigue

parameter of the Superpave ) is in tune with the results obtained from thespecification

(G*.sin analysis of the fatigue life curves.


New bitumen quality control test (QCT) for Europe

ID: 299

Dongre, Raj1, Youtcheff, John S

2, Newman, John

3

1 Dongre Laboratory Services Inc., Fairfax, United States

2 Turner Fairbanks Highway Research Center, Federal Highway Administration, Mclean,

United States

3 Laser Technology Inc., Norristown, United States


An innovative, simple, and easy-to-use test method was developed for quality control testing

of asphalt binders at the mix plant. This new method, the bitumen Quality Control Test

(QCT), uses an air jet to produce indentation and a laser deflectometer to measure the

resulting deflection. The QCT is conducted under constant stress and temperature similar to

the traditional Penetration test (ASTM D5) except instead of the penetration needle an air jet

is used with a loading time of 20s and recovery time of 50s under no load. Unlike the

Penetration test, the QCT measures both the loading and recovery characteristics of a binder.

The complete creep-recovery curve is measured and stored. The measurement of recovery

properties allows for successful discrimination of both unmodified and polymer modified

binders. The initial data demonstrating the proof of concept and within laboratory

repeatability was published recently in the proceedings of the Canadian Technical Asphalt

Association (CTAA). A possible Penetration based specification approach was also briefly

considered in the CTAA paper. In this new approach the Penetration value and the recovery

value may both be specified for bitumen. So both unmodified and modified bitumen may be

specified by merely changing the percent recovery requirement. More data has been generated

using this approach for Penetration graded bitumen from Europe and Asia. An advanced

version of the QCT test is being developed. In the Advanced Quality Control Test (AQCT)

the profile of indentation basin is characterized using the Shearography technique. In

Shearography, advanced laser technology is used to measure the velocity profile of the out of

plane displacement. Initial experiments have shown that the velocity profile generated may be

used to relate to the chemistry and rheology of the bitumen being tested. Further tests are

under way to characterize several bitumen samples with known chemistry and rheological

properties. This paper describes the implications of using the QCT for a new Penetration

based specification that is similar to the PG specification but does not require expensive

instrumentation. The progress of the AQCT method and its findings will also be discussed.


Evaluation of the Cashew Nut Shell Liquid (CNSL) antioxidant characteristics

for asphaltic materials using different aging procedures

ID: 300

Oliveira, Alessandra Honório1, Castelo Branco, Verônica Teixeira Franco

1, Soares, Sandra de

Aguiar1

1 Transportation Engineering, Universidade Federal do Ceará, Fortaleza, Brazil


The asphalt cement (AC) aging is a natural process mainly caused by volatilization of lighter

fractions and oxidation reactions. It is known that, over the years, the asphalt mixtures age

and become more rigid. This stiffening may decrease the fatigue crack resistance in asphalt

pavements, and thus, can make them more resistant to permanent deformation. The cashew

nut shell liquid (CNSL) is a "green additive", coming from a renewable and biodegradable

source and has antioxidant characteristics. In the literature, there are some studies that

highlight the CNSL antioxidant characteristics, however, few consider its application in

paving services. In this study, the CNSL is proposed as a modifier of the AC 50/70 for the

purpose of assessing their antioxidant potential. The asphalt mixes, the conventional AC and

the AC modified with 2% of CNSL were analyzed before and after various aging processes.

The asphalt mixtures were aged in different conditions: compacted and loose samples. After

the aging processes and the AC recovery, they were evaluated in relation to their empirical

and rheological properties and compared with those obtained for the virgin AC. Furthermore,

the effects of oxidative aging was analyzed by infrared spectroscopy - FTIR (Fourier

Transform Infrared) and changes in the SARA composition (Saturates, Aromatics, Resins and

Asphaltenes) through chromatography. The asphalt mixtures containing conventional AC and

AC modified with 2% of CNSL, after the aforementioned processes of aging, were

characterized mechanically using resilience modulus (RM), tensile strength (TS), fatigue life,

dynamic modulus and flow number (FN). The results for the AC tests indicate that the CNSL

acts as an antioxidant for the short-term period, but it does not show the same behavior for the

long-term period. After analyzing the results achieved for the asphalt mixtures, it can be said

that the CNSL caused a slight reduction in stiffness of these mixtures and, possibly, it was

polymerized when subjected to the oven aging process. The most aggressive process of aging

was obtained when subjecting the loose mixture to the long-term aging for nine days.


Evolution of the rheological behavior of asphalt emulsions

ID: 316

Serment-Moreno, Sergio1, 2

, Hinojosa, Moisés1, 3

, Martínez, Rosita4, Reyes, Edgar

1, 3

1 Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, San

Nicolás de los Garza, Mexico

2 Laboratorio, Proyectos Asesoría y Control de Calidad de Obras Civiles S.A. de C.V.,

Guadalupe, Mexico

3 Centro de Innovación, Investigación y Desarrollo en Ingeniería y Tecnología, Universidad

Autónoma de Nuevo León, Apodaca, Mexico

4 SemMaterials México, Cholula, Mexico


It has been more than a century since asphalt emulsions appeared in the market; nevertheless,

in Mexico its use has decreased due to the lack of knowledge, standards and regulation.

Nowadays emulsions are classified according to their breaking index; however, a direct

relation between the breaking index and the breaking process in field has not been found. On

this basis, in this research we present a new approach to study the breaking process and

measure the required breaking time of asphalt emulsions. We studied the breaking process of

emulsions using rheological measurements. Three different emulsions were studied: ECL60-

90P, ECL60-90PL (Emulsion modified by adding SB in latex) and ECL60-90PS (Modified

asphalt with SB was emulsified). Silicon-rubber recipients were fabricated in order to contain

emulsion samples. These samples were subjected to a controlled curing at three different

temperatures (30, 40 and 50°C) during 10 days for each temperature. Each day a frequency

sweep test was performed at three different temperatures (30, 40 and 50°C) in order to obtain

a Master Curve for each day. We have found that the development of the dynamic modulus

for the studied emulsions presents a similar behavior and can be adjusted to a logarithmic

equation. These results suggest that it may be possible to measure the breaking time of

asphaltic emulsions by means of rheological measurements.


Effect of polyphosphoric acid on bituminous binder oxidation

ID: 320

Glaser, Ron1, Turner, Fred

1, Onnembo, Giovanni

2, Planche, Jean-Pascal

1

1 Western Research Institute, Laramie, WY, United States

2 Innophos, Inc., Cranbury, NJ, United States


Polyphosphoric acid (PPA) has been successfully used for years in the US and other parts of

the world to enhance high service temperature stiffness of paving grade bitumen. Several

researches show evidences of PPA interaction with asphaltenes and resins. These interactions

typically lead to an increase of the asphaltene content concurrently with a decrease of the

resins content. The mechanism describes a dispersion of the asphaltene-resins phase leading

to the increase in viscosity of the bituminous binder. Whereas the impact of PPA onto the

physical properties of the asphalt at high temperature is reasonably well described, the

favorable effect reported by some authors, on bitumen aging remains unclear. In order to

study the effect of PPA on bitumen oxidation, two bituminous binders from two different

sources were treated with PPA and oxidized as thin films at 70 °C for up to 8 weeks along

with the untreated control materials. Oxygen uptake was determined by transmission Fourier-

transform infrared spectroscopy for each material, and the rates of reaction of the treated and

untreated bitumens were compared. Oxygen diffusivity differences were investigated under

the same conditions with thicker films (1000 micron). Molecular weight change differences

were measured with size exclusion chromatography. The changes in rheological properties

were examined using dynamic shear rheometry. The overall results indicate that PPA alters

the oxidation reaction mechanism compared to reference bitumen by slightly reducing the

oxygen uptake.


Low temperature and aging properites of polymer-modified binders

ID: 325

Hung, Yvong1, Dulac, Guillaume

1, Gauthier, Gilles

2, Largeaud, Sabine

3, Pouteau, Bertrand

3,

Faucon-Dumon, Stéphane3, Eckmann, Bernard

4

1 Research Center, Total Marketing and Services, Solaize, France

2 Technical Department, Total Marketing and Services, Nanterre Cedex, France

3 Research Center, Eurovia, Mérignac, France

4 Technical Department, Eurovia, Rueil-Malmaison, France


The search for a “universal” (applicable to any kind of bituminous binder) test describing the

performance of bituminous binders at low temperatures is still ongoing. Although several test

methods exist, they remain questionable and discussed, be it in relation to their reliability

(reproducibility / universality of Fraass testing) or for phenomenological reasons (e.g. no

crack phenomenon for BBR testing). Our paper presents the results of a study devoted to the

validation of different methods measuring the low temperature behaviour of bituminous

binders. This validation was performed in reference to the restrained specimen thermal

shrinkage test (TSRST) performed on an standard asphalt mix-design. In addition to both

Fraass and BBR testing, a newer method (ABCD test) for the assessment of cracking behavior

has been evaluated as well. The investigation focused on pure bitumen and binders modified

at several levels of content with an elastomeric polymer. The majority of the modified binders

have been obtained by a technique of crosslinking but comparisons were also made with

equivalent un-crosslinked physical mixture binders. Finally, an important part of the

investigation was devoted to a concomitant analysis of the sensitivity of these test methods to

the degree of aging of both binders and asphalt mixes.


New modified binder packed in block for road application

ID: 328

Lapalu, Laurence1, Mouazen, Mouhamad

1, Schroeder, Soenke

2, Gauthier, Gilles

3, Vincent,

Régis1, Colliat, Romain

1, Bobrisow, Laurent

1

1 Centre de Recherche, TOTAL MARKETING AND SERVICES, SOLAIZE, France

2 TOTAL BITUMEN Deutschland, TOTAL MARKETING AND SERVICES,

BRUNSBUTTEL, Germany

3 Direction Bitumes, TOTAL MARKETING AND SERVICES, NANTERRE, France


For decades drums have been widely used to transport bitumen in solid form into remote

geographic areas where truck delivery in bulk at high temperature (140-160°C) is not

possible, because of poor logistic and road infrastructures, or located far from hot bitumen

storage facilities. A new bituminous solution in block form has recently been developed for

such geographical areas. This patented technology is based on the addition that holds the

bitumen in block. The modified bitumen is then able to sustain load and resist creep up to 75-

80 °C. It remains solid and keeps its original shape during transport by containers and storage

at ambient temperature during several months. The bitumen is conditioned in blocks of 20-

25kg, which makes it easy to transport by sea, to store, and to dispatch to the end customer.

Another advantage is that it does not require the use of drums or other containers, avoiding

any concern regarding losses of product, leaks or waste. It is also an energy-efficient solution

because no heating is necessary during transport and storage. This bitumen in block is

designed to compete with bitumen in drums on technical, environmental and economical

grounds. It shows a significant price and transport advantage on drums any time there are

strong logistic or supply issues in a market. This paper focuses also on various technical

studies that have been carried out on the bitumen in block. All results and measurements are

in compliance with EN specifications and show that this solution performs equally when

compared to reference paving grade bitumen in terms of workability, moisture resistance,

rutting resistance, fatigue resistance and thermal cracking resistance.


Relationships between solubility and chromatographically defined bitumen

fractions and physical properties

ID: 337

Glaser, R.1, Planche, J.-P.

1, Turner, F.

1, Boysen, R.

1, Schabron, J. F.

1, Delfosse, F.

2,

Drouadaine, I.2, Faucon-Dumont, S.

2, Largeaud, S.

2, Eckmann, B.

3

1 Western Research Institute, Laramie, United States

2 Eurovia Research Centre, Merignac, France

3 Eurovia Technical Department, Paris, France


An understanding of how bitumen chemical composition influences mechanical behavior is

critical to addressing a number of practical issues concerning bitumen utilization. Using

simple chemical tests to assess bitumen quality is of practical value to the purchaser, but other

applications exist as well. Blending to achieve material design objectives is obviously of huge

industrial and commercial value, as is designing and selecting better additives. This is also

key to understanding physical changes related to bitumen oxidation and predicting

performance. Western Research Institute (WRI), in partnership with Eurovia, has examined

several paving grade bitumens using an automated asphaltene solubility fractionation method

developed by WRI under contract with the United States Federal Highway Administration

(FHWA) that is an expansion of the traditional SARA method (SAR-AD™). The results of

these chemical characterization studies were then correlated to a wide range of bitumen

properties (Penetration, Ring and Ball softening point, Dynamic Shear Rheometry, and

others) using WRI’s multivariable significance search algorithms (ExpliFit™). In general,

most properties can be explained with a high coefficient of correlation by considering a

balance between mobile and relatively immobile constituents, as well as interactions induced

by polarity and polyaromaticity. This paper focuses on the micro-structural explanation of the

significant parameters affecting the storage shear modulus over the range of temperatures

investigated. The correlation results suggest that as temperature changes, the amount of the

mobile fractions in the bitumen dominates low temperature behavior, while at high

temperatures, multiple fractions must be considered.


Bitumen quality recording - A German approach

ID: 339

Wegmann, Marcel1, Vienenkötter, Ludger

1, Pfitzmann, Marco

2

1 Global Fuels Technology Bitumen, BP Europa SE, Gelsenkirchen, Germany

2 FVC Rhine Bitumen and Coke, BP Europa SE, Bochum, Germany


The requirements of the majority of bitumen in Europe are described in EN 12591 and EN

14023. European regulation allows each country to adopt a suitable description of these in

their local norms. In Germany the requirements for EN 12591 and 14023 normed bitumen

have been transferred into TL Bitumen (TL means technical conditions of delivery) as the

national guidance paper for these standards. In an attempt to improve the description of

bitumen quality, the German government has approved a paper with additional requirements

to be measured by both supplier and user. The paper, named ARS 11/2012, contains

investigations with DSR and BBR. It was implemented into the TL Bitumen in 2013. At the

time of implementation most of the test laboratories in Germany were not used to the

methods. In this paper we describe the results from a two-step comparative study with

participants along the whole supply chain. In the first step, measurements were done with the

authorities original test procedures. Based on these results the test descriptions were modified.

In the second step, improvement of the reproducibility of the methods was investigated. A

benefit for the participants was to gain more experience with these kinds of equipment and

test methods. In this paper the results and conclusions are discussed.


Development and verification of a suitable methodology for stability

assessment of bitumen adhesion promoters

ID: 346

Valentová, Tereza1, Altman, Jan

1, Valentin, Jan

1




Durability of pavement structures represents one of the most important aspects increasingly

followed during last years. There are many reasons for this focus, most important are related

to public budget constraints and the necessity to develop or rehabilitate road infrastructure.

Since many years there has been a stress on using locally available resources which is for

asphalt related mainly to the aggregates. On the other hand bitumen comes from a

nonrenewable resource which is used to cover many demands of the world’s society. To keep

it simple, remaining byproduct is then classified as bitumen what has of course impact on its

qualities as well. In case of asphalt pavements durability is related to water and frost

resistance of the mix. The water can cause problems if adsorbed by the aggregates. This

happens if hydrophilic aggregates are used and the coating by bitumen is not good. For these

reasons different additives are used to improve coating and turn the hydrophilic state to a

hydrophobic one. Plenty of solutions are available on the market sometimes making the

decision for not easy to make a right choice. Since decades test methods have been developed

to study durability aspects, adhesion or water susceptibility. In many countries like the Czech

Republic simple methods are still used, often based only on observer’s visual opinion and

especially often qualifying only the status of a doped bitumen/mix when being produced. This

is valid for all test methods defined in EN 12697-11 and similarly also in the national test

method used in the Czech Republic. Based on this fact a research project was launched to

ideally define a suitable test procedure for evaluating thermal stability and long-term activity

of adhesion promoters if used in the bitumen and applied in a mix. This paper is describing

how the test method was selected and evaluated, what are the principles the method is based

on, if applicable only to the bitumen-aggregate coating quality or analyzing the water/water-

frost impacts more. Results are given for the tests done and for assessment of different

adhesion promoters. Test protocol is proposed at the end defining necessary conditions.


Scientific justification and effective production technologies of perspective

high-quality road bitumens at the modern enterprises with high extent of oil

refining.

ID: 353

Yakovlev, Sergey Pavlovich1, Pogulyaiko, Vladimir Anatolievich

2, Filimonov, Andrey

Valentinovich2, Pogulyaiko, Anastasya

3

1 LLC " Vokstek ", tbc, Russian Federation

2 LLC "RN Indastries", Moscow, Russian Federation

3 tbc, tbc, Russian Federation


Ensuring production of high-quality road bitumens for national and interstate roads is

becoming more difficult. . In practice most of Russian crudes are unsuitable for production of

distilled bitumens due to the high content of paraffin and the low content of petroleum

pitches. Oil refineries have resources components which can be used for producing high-

quality bitumens. A practical method to improve the quality of bitumens offered by authors is

the improvement of raw materials through oxidation by an additive of a number of products

of production of oils and other processes of crude oil processing (еxtracts and refined

selective treatment of distillate and residual lubricating base oils). The paper will describe the

decision to use of scientific optimization and techniques of quality management of production

of road bitumens. Management is conducted by control and regulation of three factors:

structure of raw materials of oxidation, kinetics of process of oxidation, composition of the

received compounded bitumen. This decision allows to influence each factor of process

adequately. The principle of control of the reactor of oxidation is based on the maximum use

of energy of the entering streams and allows to distribute it evenly on all volume of the

device. Simplicity of a design of the reactor provides low capital expenditure for its

introduction. The combination of the temperature and hydrodynamic condition of oxidation

makes it possible to manufacture a wide range of bitumens of improved quality.


Zero shear viscosity from oscillation tests on aged and non-aged bitumens

ID: 367

Puello, Juliana1, Afanasjeva, Natalia

2, Alvarez, Mario

2

1 Chemical Engineering, Universidad de San Buenaventura Seccional Cartagena, Cartagena

de Indias, Colombia

2 Chemistry, Universidad del Valle, Cali, Colombia


Bitumens are complex mixtures of hydrocarbons that show a wide range of molecular

weights. This makes bitumens to behave as viscoelastic materials, whose mechanical response

depends on the magnitude of the loads that are applied on them, as well as on the time and

temperature the loads are applied. Quality specifications for bitumens have been developed in

order to provide rational parameters for the bitumen resistance to rutting, cracking and ageing

under service conditions. Some parameters based on the complex shear modulus that are

already in use, have shown limitations when evaluating and comparing the bitumens

resistance to rutting. On the other side, the zero shear viscosity has shown satisfactory

correlation for the rutting resistance of bitumens in pavements. This work presents the

determination of zero shear viscosity for two Colombian bitumens, compared to Boscan

bitumen. Each bitumen was tested in three different ageing level (initial, rolling thin film

ageing and pressure vessel ageing). Master curves for complex viscosity versus frequency

were obtained by oscillation tests, and master curves data were fitted to three rheological

models (Carreau, Cross-Sibilsky and Cross-Williamson), by using the least squares error

method. Other parameters from the models were also estimated. It was found that zero shear

viscosity depends on the ageing level of the bitumen, while the dependence on the type of

bitumen is not significant. Besides, the three models can describe properly the relationship

between complex viscosity and frequency. The results show that zero shear viscosity can be

used as a parameter in quality specification for the three bitumens studied.


Evaluation of performance tests on bitumens

ID: 370

Vacin, Otakar1, Cerny, Radek

2, Plitz, Jiri

3

1 Czech Technical University & DuPont, Prague, Czech Republic

2 Research Institute of Inorganic Chemistry, UniCRE-EFFRET, Litvinov-Zaluzi, Czech

Republic

3 Paramo, a.s., Pardubice, Czech Republic


The trend in modern pavements is moving towards bitumens with higher performance for

longer term service in roads. There is a demand for better strength and adhesion, lesser road

maintenance and road closures. It can be observed large increase in traffic load and

application of new techniques which require more innovative binders. Hand in hand with

mentioned changes new material evaluation is taking place. Bitumen properties are more

often characterized in relation to temperature, loading time, frequency, stress or deformation.

One of the base flow techniques is a repeated creep that is measured with dynamic shear

rheometer as a tool of study of bitumen viscoelastic properties. The method is under

investigation currently and many road agencies worldwide applied the results in to the

specifications. This paper deals of the use of dynamic mechanical analysis for better bitumen

characterization at selected polymer modified bitumens as well as the evaluation of Multiple

Stress Creep and Recovery Test based on proposed prEN 16659 standard.


Testing of bitumen-aggregate affinity by various methods

ID: 397

Błażejowski, Krzysztof 1, Olszacki, Jacek

2, Peciakowski, Hubert

2, Wójcik-Wiśniewska,

Marta1

1 R&D dept, ORLEN Asfalt, Plock, Poland

2 PKN ORLEN, Plock, Poland


The affinity of bitumen and aggregates is one of the most important factors influencing

durability of the asphalt mixture and then the asphalt pavement, especially when the freeze-

thaw period occurs. There are many methods of testing this property. Presently, the method

according to EN 12697-11 (A: rolling bottles) is one of the most often used. From the other

side, the ITSR method )EN 12697-12) with one freezing cycle for asphalt mixtures testing is

used. Because there were a lot of problems with fulfilling the ITSR requirements, the

applicability of rolling bottle test was questionned. The scope of the research was to recognize

an influence of different rolling bottle test variants on the final results (durable bonding

between binder and aggregate). Generally, the mode of aggregate-binder samples’ preparation

for rolling bottle test was similar to behavior of samples in procedure with ITSR. Following

parameters were analyzed: preparation mode of bitumen (aged or not), aggregates’ soaking

with water, freezing of coating aggregates, NaCl solution presence etc. Finally, there were

found some conclusions about factors influence to results of rolling bottle test.


Towards understanding the breaking and coalescence of bitumen emulsions

for cold asphalt

ID: 402

Khan, Abdullah1, Redelius, Per

2, Kringos, Niki

1

1 KTH Royal Institute of Technology, Stockholm, Sweden

2 NYNAS Bitumen AB, SE-149 82 Nynäshamn, Sweden


Cold mix asphalt (CMA) emulsion based technology is a potential option to replace

traditional hot mix asphalt due to environmental benefits and less energy consumption of

producing it. However, there are some issues concerned with CMA, for instance, pre-mature

coalescence of bitumen emulsions while mixing with minerals or aggregates, which might

need more attention to improve the performance of CMA. Actually, the adhesion between the

binder and the aggregate surface is largely dependent on the breaking process of bitumen

emulsions and the water push-out from the mixtures. This breaking process helps to predict

the materials behavior as well as the long term mechanical performance of the mixtures;

however, the exact nature of the breaking mechanism of bitumen emulsion is not completely

understood until today. The objective of this research is to develop understanding of the

structural changes during the phase separation and coagulation stages of the bitumen

emulsion. Wettability of bitumen was analyzed by changing the substrate climate conditions.

Moreover, this study was extended with the addition of emulsifier and other additives to the

binder itself as well as to the water phase. Similar kinds of experiments were setup for

exploring the coalescence of bitumen drops in water and emulsifier with other additives.

Keywords: Cold Mix Asphalts, Bitumen Emulsions, Coalescence, Breaking Mechanism,

Wettability, Surface Free Energy.


Extended bitumen testing in Germany

ID: 403

Radenberg, Prof. Dr.-Ing. Martin 1, Flottmann, Nina

1, Koenig, Prof. Dr.-Ing. Markus

2, Hilfert,

Thomas2

1 Chair of Pavement Engineering, Ruhr-Universität Bochum, Bochum, Germany

2 Chair of Computing in Engineering, Ruhr-Universität Bochum, Bochum, Germany


In Germany conventional bitumen and polymer modified binder are mainly identified through

parameters that do not allow conclusions on its behaviour regarding temperature or detailed

rheological characteristics. Would these parameters be available (or specified), a more

targeted evaluation of the appropriate materials for each situation could be done and

eventually would lead to a better end product, i.e. road. In 2013 the German federal ministry

of Transport and Digital Infrastructure extended the bitumen testing with this objective as

follows: • Resistance to hardening under the influence of heat and air according to DIN EN

12607-1 at 163°C (penetration at 25°C and softening point) • Resistance to hardening under

the influence of heat and air according to DIN EN 12607-1 at 163°C plus an accelerated long

term aging according to DIN EN 14769 (penetration at 25°C and softening point) •

Rheological properties using dynamic shear rheometer (temperature sweep and multiple stress

recovery test) and bending beam rheometer Bitumen manufacturer perform these testings

quarterly with the conventional bitumen 30/40, 50/70, 70/100 and 160/220 and with the

polymer modified binder 25/55-55, 10/40-65 and 40/100-65, asphalt mixture manufacturer via

an extended in-house production control and contracting entity through an extended

verification audit. Around 3000 records yearly are collected by the Ruhr-Universität Bochum

with the help of a specifically developed internet-based database. The statistical evaluation

yields a very extensive overview of the rheological characteristics of bituminous binder and

may serve for specifications in future sets of rules.


Bitumen as required – the dream of a designed binder

ID: 405

Weigel, Sandra1, Stephan, Dietmar

1

1 Field Building Materials and Construction Chemistry, Technische Universität Berlin, Berlin,

Germany


The objective of this work is to bring rheological and chemical properties of the bitumen

together. As rheological investigation methods, the determination of the softening point (Ring

and Ball method) as well as the determination of the complex shear modulus |G*| and the

phase angle δ with the Dynamic Shear Rheometer were carried out. As chemical analyses, the

separation of asphaltenes to determine the asphaltene content, the further separation of the

maltene phase using column chromatography to determine the content of the saturates,

aromatics and resins and the gel permeation chromatography to determine the molecular

weight were carried out. The relationships between the rheological and chemical parameters

were investigated by multiple regression analyses. It shows inter alia that the viscosity and the

stiffness of the bitumen are dependent on both the asphaltenes and the maltene fractions. In

contrast, the deformation behaviour of the bitumen is mainly determined by the asphaltene

content. Furthermore, the contents and molecular weights of the SARA fractions provide

information about the sensitivity of ageing and the bitumen behaviour after ageing. The

findings can be of benefit for the selection of an appropriate binder for road construction and

for the recycling of bitumen.


Quantification of polymer content in binder by modified MSCR test

ID: 411

Alisov, Alexander 1, Hagner, Tobias

2, Walther, Axel

1

1 ISBS, TU Braunschweig, Braunschweig, Germany

2 Total Bitumen, Brunsbüttel, Germany


The Multiple Stress Creep and Recovery Test (MSCRT) is a testing method using the

dynamic shear rheometer (DSR) to determine viscoelastic and viscous binder properties in

order to assess the influence on the asphalt deformation behavior. The applicability of the test

conditions and the corresponding simplified evaluation method formulated in the standards

are reviewed in this paper. Here, rheological analyses are performed of the creep recovery

curves corresponding to the Burgers model. The results of MSCRT prove that the viscous

behavior of the binder is sufficiently described under the defined test conditions. However,

the viscoelastic behavior may be determined more precisely at equi-viscose temperature.

Further on the modification of the test enables to assess the effectiveness of the polymers

contained in the bitumen on the one hand or the polymer content on the other.


An evaluation of aging of polymer-modified asphalts

ID: 413

Largeaud, Sabine1, Faucon-Dumont, Stéphane

1, Eckmann, Bernard

2, Hung, Yvong

3, Lapalu,

Laurence3, Gauthier, Gilles

4

1 Centre de Recherche, Eurovia, Merignac, France

2 Direction Technique, Eurovia, Paris, France

3 Centre de Recherche, Total Marketing and Services, Solaize, France

4 Direction Bitumes, Total Marketing and Services, Paris, France


Due to budget constraints in Europe, sustainability of pavement materials is taking an

increasing part in the construction and maintenance policy of road networks. The aging

properties of bituminous binders are known to have a direct impact on the durability of road

pavement and must be properly assessed. The measurement of in-situ bituminous binder and

asphalt mix performances is the most reliable way to appreciate and measure the consequence

of aging and oxidation on materials. However, accelerated test methods provide a cost-

efficient, predictive assessment of the aging behavior, provided that these methods are

representative of the aging phenomenon in the field. The present study is focused on the low-

temperature and the aging properties of various bituminous binders in relation to the

corresponding properties of asphalt mixes. In a first publication, investigations were devoted

to different binder’s characterization method (Fraass, BBR, ABCD) as potential predictive

tool to thermal cracking of asphalt mixtures (TSRST). This paper focuses on analyzing the

sensitivity of these test methods to the degree of aging of different binders (paving bitumen,

crosslinked elastomer-modified binder and physical blend elastomer-modified binder) and

asphalt mixes. Based on original investigations, noticeable trends are pointed out aging

impact on binders and both methods.


6. Mixture performance and testing

Effects of fiber reinforcement on the fatigue and rutting performance of

asphalt mixes

ID: 15

Weise, Christiane1, Zeissler, Alexander

1

1 Institut of Urban and Pavement Engineering, TU Dresden, Dresden, Germany

Topic: 6. Mixture performance and testing

Fatigue, stiffness and rutting characteristics have a major influence on the pavement

performance. For this reason different fibers are currently in use to investigate the impact of

loose fiber reinforcement on the performance characteristics of asphalt mixtures. This paper

presents tests of the fatigue, stiffness and deformation characteristics of different asphalt

mixes. An asphalt base mix AC 22 T S (3 variations) and a stone mastic asphalt SMA 8 S (8

variations) were chosen to determine the effect of fiber reinforcement on fatigue and rutting

performance. The test results show the influence of the chosen fibers (cellulose and

Polyacrylonitrile PAN) on the material characteristics mentioned. On the one hand the

difference between the mastercurves is insignificant concerning fiber use. On the other hand it

is obvious that the fibers significantly influence the fatigue behavior. The impact of

reinforcement is also illustrated using the German pavement design process. The use of fibers

allows a road base layer reduction by up to 6 cm without compromising the safety level. The

plastic deformation value can be reduced to 42% depending on fiber type and quantity.

Further improvement can be achieved by inserting polymer modified bitumen, which reduces

the plastic deformation value to approx. 64%.


Study of UV rays effects on the evolution of bituminous mix behaviour

ID: 27

Mouillet, Virginie1, Farcas, Fabienne

2, Sauger, Jaurent


2

1 Laboratoire d'Aix-en-Provence, CEREMA / DTer Méditerranée, Aix-en-Provence cedex 3,

France

2 Division Matériaux, IFSTTAR, Bouguenais Cedex, Bouguenais Cedex, France

3 Laboratoire Régional de Lyon, CEREMA / DTer Centre-Est, Bron Cedex, France


During their lifetime, asphalt layers are subjected to aging. Recently, attentions have been

paid to the laboratory ageing tests with UV radiation applied to the bituminous binders but

there are few studies dealing with the photo-oxidation of binders in a bituminous mix. So, the

aim of this study was to investigate whether the influence of ultraviolet light on bitumen

ageing might be assessed in the bituminous mixes using an experimental apparatus dedicated

to the ageing of paint. The results show that the influence of UV radiation on the ageing of

bituminous mixes containing an elastomer modified bitumen cannot be totally ignored:

compared with thermal aging, the UV impact can be found to be dominant for the production

of carbonyl functions, the disappearance of C=C double bond of SBS and the increase of

binder’s hardening. This study has highlighted, on the one hand, that inside the bituminous

mix, the UV radiations do increase the rate of oxidation and, on the other hand, that the

evolution’s kinetics due to a pure thermal oxidation or a photo-oxidation processes are

different. Consequently, the UV exposure may affect the bitumen’s properties of pavement

upper layers more strongly than the laboratory test (without UV action) does.


Update on new and future CEN asphalt test methods

ID: 34

Nicholls, Cliff1, Lind, Kenneth

1

1 Infrastructure Division, TRL Limited, Wokingham, United Kingdom


EN 12697 is an extensive series of European norms for test methods and preparation

procedures. Since the introduction of the harmonised asphalt specifications were published in

2006 (which required theses test methods to be applied), several additional test methods have

been published. These tests are crack propagation by semi-circular bending test, saturation

ageing tensile stiffness (SATS) conditioning test, low temperature cracking and properties by

uniaxial tension tests, determination of the ash content of natural asphalt and determination of

friction after polishing. In addition, tests for interlayer bond strength, conditioning to address

oxidative ageing, cohesion increase by spread ability-meter method (for cold mix asphalt),

resistance to scuffing and surface shear strength test are being standardised. The paper will

review these test methods in terms of why they are required, what options are covered by the

draft, what the principal of the method and, for those still to be published, how far through the

CEN system that the draft has reached.


Laboratory simulated asphalt ageing: Myth or reality?

ID: 40

Besamusca, Jeroen1, Hoogendoorn, Marijke

1, Jacobs, Maarten

2, Rering, J

2, Poeran, Natascha

3,

Sluer, Berwich3

1 Kuwait Petroleum Research & Technology, Kuwait Petroleum International, Europoort

(Rd), Netherlands

2 Technology & Development, BAM wegen, Utrecht, Netherlands

3 MNO Vervat wegen, Boskalis, Nieuw-Vennep, Netherlands


The oxidation of the asphalt binder is thought to be one of the most important aspects of the

durability of paving. For more than 40 years the simulation of oxidation is tested in laboratory

by binder ageing tests like RTFOT, TFOT, RCAT, PAV and other methods used.

Unfortunately simulation of real asphalt cores or plates is still under investigation and no

standardised test has been approved. At the time of writing prEN 12697-52 is launched for

comment and suggests two conditioning methods. The first is a loose mix ageing and the

other asphalt core ageing. The research reported here started as a search for a representative

simulation of open graded asphalt ageing. Several asphalt aging conditionings have been

tested and analysing binder recovered showed the influence of the ageing conditioning.

Binders were analysed on mechanical (empirical and rheological) and chemical

characteristics. The results are compared with previous reported research on binder ageing

and field aged material. The results showed that the general idea of simulating ageing by high

temperature oxidation as most important aspect should be taken into consideration. It is found

that high temperature laboratory conditioning of open graded asphalt cannot simulate asphalt

field ageing. All tests results ranked the different laboratory ageing conditioning more or less

in the same order. But mechanical results were always less than field aged material while

chemical characterisation clearly showed that certain ageing conditions were beyond the field

aged material. It is also found that a small amount of extraction liquid influences the results of

analyses and therefore a headspace test should be introduced at research working with

recovered binder. This should also be taken into account when contractors work with RAP

material and calculate the amount of new binder based on the test results of extracted RAP

binder.


Effect in the high modulus asphalt concrete with the temperature

ID: 46

García Hernández, Maria Inmaculada1, Shahri, Abbas

1

1 Construction Engineering, Uppsala Universitet, SE-751 21 Uppsala, Sweden


SYNOPSIS The use of the High Modulus Asphalt Concrete in the base course of airport

pavements is not of recent utilization, but at present there is a considerable gap in the

regulation for the use of this bitumen. The main objective of this paper is to present the results

of the research that has been done using the experimental dynamic modulus of different

mixtures of conventional bitumen with different penetration index B40/50, B60/70,

B100/150, B150/200 and the high modulus bitumen B13/22 to calculate the percentage of

reduction in thickness of the base course in airport pavements when is used High Modulus

Asphalt Concrete (HMAC) compare with conventional bitumen mixtures and is also taken

into account the temperature. In order to obtain the reduction in thickness depending on the

temperature and the use of HMAC, the tests have been performed at the different

temperatures -20°C, -10°C, 0°C, 10°C, 20°C and all the results in this paper are presented for

these temperatures. To perform the calculations of this research the Airbus A380 has been

taken as Aircraft Design. Keywords: Runways, Airports, High Modulus Asphalt Concrete.


Influence of hydrated lime on the field performance of SMA10 mixtures

containing polymer modified binder

ID: 67

Vansteenkiste, Stefan1, De Visscher, Joëlle

1, Denayer, Christophe

2

1 Asphalt Pavements, Bituminous Applications and Chemistry, Belgian Road Research

Centre, Brussels, Belgium

2 Carmeuse Coordination Centre, Louvain-la-Neuve, Belgium


In literature, the beneficial effect of hydrated lime on the durability of asphalt mixtures has

been demonstrated extensively, especially while performing laboratory testing. However,

experimental evidence on the impact of hydrated lime in combination with the use of polymer

modified bitumen (PmB) on the field performance of an asphalt pavement is rather scarce.

Therefore, an initiative was taken to set up a test program of which the main objective was to

gain as much as possible experience from the field.Hence, the comparative study focused on

the assessment of the performance of SMA10 variants by the construction of test sections in

combination with a series of laboratory tests. The impact of hydrated lime on the performance

of SMA10 variants was investigated at different stages. Prior and during the construction of

the test sections, the effect of hydrated lime on the workability was monitored by carrying out

either gyratory compaction tests in the laboratory or by a follow up of the in situ compaction

by making use of -nuclear gauge. Following construction, appropriate test specimensthe

were taken by coring in order to probe for the resistance to rutting, the water sensitivity and

finally the resistance to ravelling. This paper discusses and draws conclusions from this

comparative field study with respect to the use of hydrated lime in SMA10 mixtures

containing a polymer modified bitumen.


Rutting potential and texture of thin asphalt layers

ID: 68

Nielsen, Erik1

1 Pavements, Vejdirektoratet (Danish Road Directorate), Hedehusene, Denmark


Development and optimizing of mix design for thin asphalt surface layers with functional

capabilities (i.e. noise reduction, low rolling resistance) is a laborious task with several loops

from laboratory mix design to test section before a real progress can be achieved. To this end

it will be highly advantageous if some screening of mix design can be performed in the

laboratory which can indicate the path of development of optimal candidate mixes for full

scale test sections for the final optimization. Maintenance of existing infrastructure often calls

for thin asphalt layers to provide the abovementioned functionalities on milled surfaces of old

asphalt pavements. Decision of the thickness of the new asphalt layer can be a challenge due

to the rough texture of the substrate. On one hand if the applied layer thickness is too high

you may risk the occurrence of permanent deformations (rutting). On the other hand if the

layer thickness is too small you risk poor durability. This study evaluates the use of the

texture profiles with high resolution laser measurements on laboratory compacted slabs of

various thicknesses for Wheel Tracking Test with texture profiles of full scale pavements on a

number of thin asphalt layers with functional capabilities.


Hydrated lime as additive for increased durability of asphalt mixes even after

recycling

ID: 69

Ritter, Hans-Josef1, Westera, Gerrit

2, van der Bruggen, Peter

3

1 Federation of German Lime Industry, Cologne, Germany

2 Koac-Npc, Apeldoorn, Netherlands

3 Koac-Npc, Vught, Netherlands


The paper to be prepared presents the results of a laboratory testing programme on the

beneficial effects of hydrated lime in binders of a recycled dense asphalt mix with a

greywacke aggregate. The hypothesis is that hydrated lime slows down the ageing process of

the asphalt mix. The test programme consisted of an ageing stage and a properties testing

stage. Various cycles of preparing mixes, cooling down, heating up, mixing again, etc. were

used to simulate the ageing process in practice. Only one type of dense asphalt mix was

tested. Both mixes with and without hydrated lime in the binder were used.The degree of

ageing was quantified after the ageing cycles 1 and 5. The asphalt specimens were gyratory

compacted. The indirect tensile test was used for characterization of the strength of the asphalt

mix. Due to ageing, the indirect tensile strength will increase with number of ageing cycle.

Compared to the reference mix (without hydrated lime) the rate of increase of the mixes with

hydrated lime in the binder was expected to be smaller than for the control mixes. The binder

properties penetration and softening point were determined to support the effect.


Production and durability of cold mix asphalt

ID: 74

Lundberg, Roger 1, Jacobson, Torbjörn

2, Redelius, Per

3, Östlund, Jenny-Ann

3

1 NCC Roads, Umeå, Sweden

2 Trafikverket, Stockholm, Sweden

3 Nynas AB, Nynäshamn, Sweden


In the nineties research started with the aim to develop robust technologies, allowing

production of asphalt at ambient temperature. Such technologies results in significantly lower

energy consumption and carbon emissions during asphalt production. The technology

investigated and discussed here is based on gentle addition of bitumen-emulsion to

aggregates, followed by controlled breaking of the emulsion on the road. However, despite

some early success with a number of roads installed using emulsion based cold mix asphalt

the market development of such materials failed to progress. Interest was also lost due to a

significant drop in energy costs in the end of the nineties. In 2012 the Swedish road authority

started an industry project to improve the understanding of cold mix design, production and

performance and demonstrate the benefits of the technology on heavily trafficked roads. A

strong relationship was found between surface area, chemical composition of stone aggregates

and breaking rate of emulsions. This understanding has the potential to significantly improve

the ability to design asphalt mixes that will be easy to produce and lay. Heavily trafficked test

roads have been produced in the last two years with cold mixture asphalt as the base course.

Further, durability data from roads produced fifteen years ago will be presented. It can

visually be seen that the roads have survived over the years without any significant signs of

aging. Analysis of the binders confirms that age hardening over time is limited, indicating the

bitumen ages slowly in the road despite of high void contents.


Experience with asphalt pavement on the heavy loaded port area of the

“Niedersachsenkai”

ID: 76

Schäfer, Volker1, Rosauer, Verena

2

1 Schäfer Consult, Brake, Germany

2 Rosauer, Cologne, Germany


From 2008 to 2012 the Brake port was expanded by the “Niedersachsenkai”. Brake is located

in northern Germany between Bremen and Bremerhaven, 26km upstream from the outlet of

the river Weser to the North Sea. At the Niedersachsenkai mainly iron/steel, project and

general cargo are handled. Pavements of industrial ports such as the Niedersachsenkai have to

be adapted to the very heavy loading resulting from storage as well as loading of the cargo on

the one hand and to the corresponding traffic. In the context of the load itself, the storage area

has to be very bearable, resistant to deformation and to ageing, and durable. Furthermore it

has to possess particularly evenness and no bumps, offsets, or edges in order to allow high

transportation speed, thus fast dropping and loading of the ships. The design life of the

pavement was set to 45 years. The structure was computationally dimensioned, which was

done for port areas for the first time. It consists of: asphalt surface course out of AC 16 with

polymer-modified bitumen and additives, asphalt base course out of AC 32 with standard

bitumen and 30M.-% reclaimed asphalt, crushed aggregate base course, and a course out of

dredged sand. The existing cargo stored on the pavement induces vertical stresses up to

3.3N/mm² depending on storage and bearing, but should not exceed 2N/mm² for a longer time

to avoid slight deformation. Higher and appropriate requirements on both the mixture and the

courses assured a high quality, homogenous, dense, and even asphalt pavement that offers

high durability, bearing capacity, and resistance to deformation as proven in practice so far.

Owing to these very good results, the pavement concept was adapted to further port

construction projects already. The paper presents the background of pavement design, the

realization of the requirements and specifications to construct a durable pavement, and

findings from the six years usage.


Evaluation of durability of the asphalt-concretes under static fatigue

ID: 78

Zolotaryov, Victor 1, Ali Al-Shalout, Imad

2



2 Civil Engineering Department, Zarqa University, Zarqa, Jordan


Forecasting the durability of asphalt- and polymer concretes which is actual in the aspect of

the eternal (or high durability) roads concept is executed in recent years on the basis of the

testing results under cyclic loading on bending with constant amplitudes of stress or

deformation. Such tests are rather complicated, expensive and ambiguous because of the

difficulties with providing symmetrical loading with respect to the zero value stress. It is far

easier to determine the asphalt concretes lifetime from the begining of loading till the total

destruction of the sample by means of double-point loading via series of constant loads (the

static fatigue while creeping). As a result a dependences similar to Woehler diagrams are

received. Analysis of literature reveals that dependences of a number of cycles and times of

destruction via stress for the same objects have close values of exponents (they are almost

similar) in case of relatively congruous stressed states and temperatures. In this case the

objectively equitable lifetimes of various asphalt-concretes can be achieved under the equal

levels of stressed state which are defined by the ratio of the quantity of stress which is

imposed on the asphalt concrete sample to the asphalt-concrete strength at the preset speed of

deformation. The available lifetimes range from 10 seconds to many days. This allows to

detect the lifetimes under near-critical stresses which correspond to the boundary of the

transition to the linear viscoelastic behavior of asphalt concretes at a wide range of

temperatures as well as under the simultaneous effect of stresses and liquid corrosive media

(water, water solution of deicing agents, oil and lubricants etc.).


Evaluation of tools for measuring the workability of bituminous asphalts

ID: 89

Fabre des Essarts, Angélique1, Dony, Anne

1, Faucon-Dumont, Stéphane

2, Gaudefroy,

Vincent3, Roux, Jean Noêl

4

1 Université Paris Est, IRC, ESTP, CACHAN, France

2 Centre de Recherche, EUROVIA, MERIGNAC, France

3 IFSTTAR, MAST , LUNAM University, NANTES, France

4 Université Paris Est, Laboratoire Navier, CHAMPS-SUR-MARNE, France


Since the beginning of 2000’s, the development of WMA, Warm Mix Asphalt, allowed the

Road companies to meet expectations regarding sustainable development by lowering the

fabrication and laying temperatures (reduction of 30 to 50°C). However, this development

also highlighted, on the jobsite, an unidentified problem with HMA, Hot Mix Asphalt: a

lesser workability during mechanized and especially manual laying, for several WMA

processes. This experimentation, part of research thesis results, aims to study the development

of a relevant and discriminating test for the evaluation in laboratory of the workability of

bituminous asphalt. Two ways were explored; the one uses a classic equipment of road

laboratories, the GSC, Gyratory Shear Compactor test, by varying the parameters ( vertical

strength, rotation speed); the other one is based on the use of the workability device called

“Nynas”, from now European standardized, with varied parameters. The work was conducted

on the same classic asphalt formula with different bitumen grades, and variable temperatures

of manufacturing. This parametric study allowed, first of all, to confirm the reduction in

workability of asphalts with the reduction in the temperature of manufacturing. It showed the

limits of the GSC, a very good test for compactibility but not for workability of asphalt. It

also highlighted the interest of the Nynas workability device after a good choice of test

parameters for a real relevance of the test result.


Multivariate statistical analysis of low temperature properties obtained from

laboratory tests on asphalt mixtures

ID: 91

Hribar, Dejan1, Tušar, Marjan

2

1 TPA za zagotvaljanje kakovosti in inovacij, STRABAG d.o.o., Ljubljana, Slovenia

2 National Institute of Chemistry Slovenia, Ljubljana, Slovenia


The paper presents multivariate statistical analysis on data obtained from low temperatures

laboratory tests on Stone mastic asphalt (SMA) mixtures. Data were gathered from four

renowned road laboratory institutes in Europe. Mainly two methods were used for statistical

analysis of data: Principal component analysis (PCA) and Partial least squares (PLS). The

PCA method was used for studying interdependence between measured low temperature

properties (TSRST, UTST and tensile strength reserve). With first two principal components

72.14% of variability in data was explained. With loading plot of first two principal

components correlations between low temperature properties were presented. The scores plot

was used to examine possible variation between different laboratories. We did not find any

systematic difference between participating laboratories. With PLS analysis dependence

between input variables X (TSRST σcry,f, TSRST Tf, UTST 5 °C, UTST −10 °C, UTST −25

°C) and output variables Y (Δβtmax, TΔβtmax) was evaluated. We found that UTST −10 °C

and UTST −25 °C Δβtmax are correlated with Δβtmax and TSRST Tf is correlated with

TΔβtmax. The paper presents also a statistical model for prediction low temperature

properties of asphalt. Model demands only three input variables (TSRST σcry,f, TSRST Tf

and UTST −10 °C) instead of five to get the same characterisation of asphalt low temperature

properties.


The Effects of Geosynthetics on Mitigation of Rutting in Flexible Pavements

ID: 101

Guler, Erol1, Atalay, Ismet

1

1 Civil Engineering, Bogazici University, Istanbul, Turkey


One of the important problems associated with asphalt concrete pavements is rutting. This

phenomenon is mostly illustrated as a surface depression in the wheel paths due to load-

induced conditions as well as improper mix design or insufficient compaction of hot-mix

asphalt. Some of the latest techniques for mitigating the severity and/or decreasing of

permanent deformations on asphalt concrete pavements, in other words, preventing the

occurrences of wheel path ruts include incorporating geosynthetic products into pavement

structure. The purpose of this study is to investigate the benefits of applying geosynthetic

reinforcement for rutting mitigation in asphalt concrete pavements by testing several

combinations of geosynthetic reinforcement types and pavement types. In this experimental

study, rut depth measurements have been taken from a “Wheel Tracking” test using Hamburg

Wheel Tracking Device (HWTD). The HWTD measures the combined effects of rutting and

moisture damage by rolling a rubber coated wheel across the surface of an asphalt concrete

specimen that is immersed in heated water. In the tests to understand the effect of the

pavement type, three types of mix designs has been used: 1) Stone Mastic Asphalt (SMA), 2)

Dense Graded Hot Mix Asphalt (HMA), and 3) Dense Graded Binder HMA. SMA, Dense

Graded HMA and Dense Graded Binder HMA mixes were prepared in laboratory from

beginning to end. Controlled material samples were used for specimens in the same group.

Mix gradation of all Asphalt Specimens was designed according to EN standards. Four

different types and brands of geosynthetic materials were used as reinforcement to provide a

resistance against rutting. Two Polyster geogrids from different producers and two Fiber

Glass geogrids again from different producers have been used in the study. The contribution

of this study to the state of the art is to present a new laboratory study and its findings to help

better understand rutting occurrence in asphalt concrete layer and its mitigation with the use

of geosynthetic reinforcement. Test results have shown that the benefit obtained by using

geosynthetic reinforcement cannot be directly linked to the tensile strength or stiffness of the

geosynthetic reinforcement.


Evaluation of rutting performance of asphalt mixtures using Extra-Large

Wheel Tracking and 2-D imaging technique

ID: 102

Ahmed, Abubeker Worake1, Arshadi, Amir

2, Erlingsson, Sigurdur

1, 3, Bahia, Hussain

4

1 Pavement Technology, The Swedish National Road and Transport Research Institute (VTI),

Linköping, Sweden

2 College of Engineering, University of Oklahoma, Norman, OK 73071, United States

3 Faculty of Civil and Environmental Engineering, University of Iceland, Reykjavik, Iceland

4 Department of Civil and Environmental Engineering, University of Wisconsin-Madison,

Madison, United States


The internal aggregate structure provides the load carrying skeleton of the asphalt mixtures,

which plays a leading role in the rutting resistance of pavements. The main objective of this

study is to investigate the application of two-dimensional (2-D) imaging and analysis

technique to evaluate the role of aggregate packing in rutting performance of three different

types of asphalt mixtures. The 2-D images are derived by scanning the cross sections of

cylindrical samples taken from asphalt slabs which have been tested using an Extra-large

wheel tracking device. Samples from loaded and unloaded areas of the slabs are analyzed to

assess any difference in aggregate re-orientation and segregation effects. The mixture rutting

performance is evaluated based on the total length of the contact between the aggregate

particles which is derived from the image analysis. The software system called IPAS2 (Image

Processing and Analysis Software) developed in previous studies is used to process the

images of the asphalt mixtures with different gradations and binder contents. The results

demonstrate a clear correlation between the internal structure indices and the mixture rutting

performance. Such results can explain the significant role of aggregate structure in rutting of

pavements.


Asphalt for heavily loaded pavements

ID: 103

Tušar, Marjan1, 2


2 Slovenian National Building and Civil Engineering Institute, Ljubljana, Slovenia


On the surface of asphalt pavements two types of damages are most common, namely the

cracking and rutting. Surface cracking, which initiate at the surface of the wearing layer of

asphalt, occurs most frequently, because a binder at low temperatures becomes too fragile.

Rutting occurs at elevated summer temperatures, due to low viscosity of binder insufficient to

sustain high traffic loads. As the binder in the asphalt layers mostly paving grade bitumen is

used, which has a relatively small temperature range between too low and too high viscosity

to withstand heavy loads. To increase the temperature range of bitumen in the bitumen

various so-called modifiers are added. Most often SBS (styrene-butadiene-styrene block

copolymer) is used to modify bituminous binder for higher traffic roads. SBS increases

quality of asphalt, but it has many drawbacks; modifier is expensive, producer have to

increase temperature when producing SBS modified asphalt mixtures and laying of asphalt

course with SBS modified bitumen is more difficult than with paving grade bitumen. In this

study, we found that the addition of Poly-methyl methacrylate/aluminium trihydrate

(PMMA/ATH) composite in the asphalt mixture increases the resistance of asphalt layers to

permanent deformations and increases durability of asphalt. With laboratory trials we

managed to reduce proportional rut depth by a factor of three, when PMMA/ATH composite

was added to bitumen. The highest degree of resistance to the formation of ruts, which was

five fold lower than in the reference asphalt layer was achieved by adding a combination of

PMMA/ATH composite powder and paraffin waxes in the bitumen. Already in 2009 test

fields were built. First dry process of adding PMMA/ATH composite to asphalt mixture was

applied and in 2013 wet process of adding PMMA/ATH composite to bitumen was utilized.

Produced asphalt was successfully built in test fields and regular roads. In comparison to SBS

we found some advantages of adding PMMA/ATH in the asphalt: cheaper additive, easier

production of modified binder, there is no need for an elevated temperature at asphalt

production, asphalt did not stick to shovels and it was found out that workability of asphalt is

even improved.


Mechanical behaviour of asphalt mixtures with steel slag aggregate for

construction to be used in road pavement layers

ID: 108

Freire, A. C.1, Lopes, M. G.

2, Andrade, R.

2

1 Transportation Department, Laboratrório Nacional de Engenharia Civil (LNEC), Lisboa,

Portugal

2 Civil Engineering Department, Instituto Superior de Engenharia de Lisboa (ISEL), Lisboa,

Portugal


Most transport infrastructures, in particular road and airport pavements, include bituminous

mixtures which allow a good performance and an adequate durability under service

conditions. On the other hand, and considering that the current EU policy for residues is based

on the guiding principle of hierarchy, supported by an integrated system of waste

management, giving priority to prevention, recycling and, only as a final solution disposal,

and knowing beforehand that preventing the production of steel slag is not feasible, the waste

management strategy should focus on its recovery, mainly through valorisation and recycling

solutions. The incorporation of steel slag aggregates in bituminous mixtures will contribute to

a sustainable development, reducing the amount of waste disposal in landfills, hence creating

a new national market and therefore preserving the environment by reducing aggregate

exploitation and associated energy consumption. Based on the European standards for natural

materials, laboratory tests were performed to characterize and classify this type of material.

The definition of the laboratory tests to be carried out, as well as the selection of the most

appropriate techniques must be supported on existing experience related to natural materials

but with the necessary adaptations to steel slag characteristics. As a methodology to study the

mechanical behaviour of bituminous mixtures with steel slag aggregates, laboratory repeated

loading tests were performed, in particular four-point bending tests (4PBT) to determine

stiffness and fatigue behaviour, and wheel-tracking tests to evaluate the permanent

deformation behaviour. The fatigue behaviour of studied bituminous mixture was evaluated

by the 4PBT, under controlled strain and the application of a sinusoidal loading with different

frequencies, according to EN 12697-24. The permanent deformation behaviour of the mixture

was determined in accordance with EN 12697-22. Water sensitivity tests according to method

A of EN 12697-12 were conducted to evaluate mixture behaviour under water conditions. The

results obtained have shown that the studied mixture AC20 base 50/70 (MB) to be applied as

a macadam layer presents an adequate behaviour, namely regarding fatigue and permanent

deformation.


Performance assessment of hot mix asphalt with chemically stabilized rubber

bitumen

ID: 110

Toth, Csaba1, Petho, Laszlo

2, Geiger, Andras

3, Soos, Zoltan

1

1 Department of Highway and Railway Engineering, Budapest University of Technology and

Economics, Budapest, Hungary

2 ARRB Group Ltd., Melbourne, Australia

3 MOL Plc., Budapest, Hungary


The use of crumb rubber from vehicle tyres in hot mix asphalt production has been a very

promising option in the field of waste recycling and sustainability. The disposal of used

vehicle tyres has been a serious and difficult issue. Due to their indestructible nature the

options are burning or disposal, none of these are desirable in our global environment. The

trials for using crumb rubber in hot mix asphalt started in the 1920s; these early applications

used the so called dry method, where the rubber is considered as part of the aggregate instead

of the binder. This method did not deliver the expected higher performance, and researchers

have been looking into the so called wet process since the 1960s, where the rubber is added to

the binder, modifying its properties. The modified binder is then added to the aggregate

during asphalt production. Although many countries utilise the crumb rubber using the wet

process, there is an ongoing problem with this technology, similarly to the application of

polymer modified bitumens (PmBs): the storage stability of the product. This short-term

segregation problem has been preventing the wide application of crumb rubber bitumen in

road construction. Additionally, the high viscosity of product may cause difficulties during

manufacturing and paving which should be considered when selecting aggregate grading.

MOL Plc. developed and patented a procedure for producing chemically stabilized rubber

bitumen (CSRB); the pilot scale production started in 2012 and the facilities are capable to

produce 5000 tonnes of CSRB – equivalent of 150,000 tyres – in their Zala Refinery,

Hungary. This paper discusses an asphalt research program conducted at Budapest University

of Technology on a 10mm nominal aggregate size wearing coarse hot mix asphalt. This study

presents the comparative analysis of asphalts containing PmB and CSRB separately. Prepared

samples were subjected to performance based and related mechanical testing. The findings

summarised in this paper suggest that performance of asphalt mixes produced with CSRB

binder are similar or equivalent to asphalt mixes produced with PmB with regard to moisture

sensitivity, stiffness and wheel tracking, while the low temperature cracking test showed

higher and superior performance.


Shear Box Tester for Characterization of Polymer Modified Bituminous

Mixtures

ID: 119

Ahmed, Abubeker Worake1, Said, Safwat Fadhil

1, Lu, Xiaohu

2

1 Pavement Technology, The Swedish National Road and Transport Research Institute (VTI),

Linköping, Sweden

2 Product Technology, Nynas AB, Stockholm, Sweden


Dynamic shear modulus is one of the primary viscoelastic parameters used as an indicator of

the resistance to permanent deformation of asphalt mixtures. The present paper describes a

recently developed shear box testing device for determining the dynamic shear modulus and

phase angle of asphalt concrete mixtures. The shear box tester was used to obtain the dynamic

shear modulus of several types of conventional and polymer modified (using Styrene-

Butadiene-Styrene (SBS) and Ethyl Vinyl Acetate (EVA)) asphalt concrete specimens drilled

from a test pavement structure soon after opening the road and 6 years later. The results from

the shear box tester were evaluated based on the performance ranking of the mixtures from

other standard mixture performance testing procedures: the indirect tensile (IDT) stiffness and

repeated load creep tests and field rut depth measurements. It was observed that both the IDT

stiffness tests and the repeated creep tests produced a ranking of the mixes similar to that

obtained from dynamic shear modulus tests at low to intermediate temperatures and high

temperatures, respectively. It was concluded that the shear box testing device is a reliable

means of measuring the shear modulus and phase angle of asphalt concrete mixtures for over

a broader range of temperatures and loading frequencies. Moreover, the mechanical tests

indicated that the unmodified mixes exhibited considerable ageing and it was demonstrated

that the SBS modified surface and binder mixes were the least affected by ageing.


Improving durability and functionality retention of porous asphalt by using

high performing bituminous binders

ID: 123

Jellema, Erica1, Vonk, Willem

1

1 Kraton Polymers Research BV, Amsterdam, Netherlands


Porous asphalt is a popular type of asphalt pavement in Europe and other parts of the world.

Its well-known functional benefits are water drainage and reduction of splash and spray,

which increases safety on the road. Moreover, the use of porous asphalt can significantly

reduce traffic noise. However, porous asphalt has a shorter life-time compared to more dense

asphalt mixes, due to the higher ageing rate, especially when the initial pavement quality is

poor or under severe weather conditions. In Japan, the quality of porous asphalt has been

successfully improved by the use of binders modified with high concentrations of SBS (8% or

higher). Although this approach to prevent raveling and clogging is successful, it has not been

widely adopted outside Japan. In the literature, the use of (SBS) modified binders for porous

asphalt has been investigated, but these investigations are often focused on the damage

profile, while the functional attributes (e.g. hydraulic conductivity or water drain capacity) are

not always taken into account, which can lead to a distorted view. In this paper, we discuss

lab and field data of the use of (highly) SBS modified bitumen compared with unmodified

bitumen for porous asphalt applications. These data make clear that in porous asphalt research

both the durability and the functionality of the asphalt should be evaluated. Furthermore, we

show the benefits of using highly SBS modified bituminous binders, especially during winter,

which was investigated using the Lifetime Optimisation Tool (LOT), developed by the Delft

University of Technology.


Evaluation of permanent deformation in asphalt mixtures composed with red

mud as filler

ID: 126

Lima, Mayara Sarisariyama Siverio 1, Thives, Liseane Padilha

1

1 Departmente of Civil Engineering, Federal University of Santa Catarina, Florianópolis,

Brazil


Red mud is a solid waste originating from the production of aluminum during bauxite

processing. Currently in Brazil this sub-product does not receive appropriate destination in

nature and is stored in deforested areas. Annually, approximately 11 million tons of red mud

are generated just in Brazil and represent a great imminent risk of pollution and

contamination. The large amount of red mud generated by the aluminum industry has

motivated researchers to develop residue insert methods in the production cycle. Studies

shows the possibility of using red mud to compose ceramic materials, however, there is a lack

of research in other areas, such as applied to pavements. On the other hand, Brazilian

highways are, in more than 50%, in poor condition, especially in the north, where high

temperatures favor the spread of permanent deformation in the pavement. In this scenario, this

paper describes the evaluation of the introduction of red mud as filler in asphalt mixtures, in

order to apply it in the production cycle and mitigate the environmental damage caused by

improper disposal. Waste characterization tests and evaluation of asphalt mixture with red

mud permanent deformation were performed. The possibility of red mud introduction as a

component in asphalt mixture and this ability to improve the mechanical strength was

evaluated. The results showed that it is possible to use the red mud on asphalt mixtures

without problems of the environment contamination.


Biasing effects (non-linearity, self-heating, thixotropy) occurring during

fatigue tests on bituminous mixtures

ID: 138

Mangiafico, Salvatore1, Sauzéat, Cédric

1, Di Benedetto, Hervé

1, Pouget, Simon

2, Olard,

François2, Planque, Luc

3

1 Université de Lyon, ENTPE (LGCB), LTDS (CNRS UMR 5513), Vaulx-en-Velin, France

2 EIFFAGE Infrastructures - Direction R&D, Corbas, France

3 BP France - Service bitumes, Cergy Pontoise, France


The study presented in the paper focuses on the evaluation of biasing effects occurring during

laboratory fatigue tests on bituminous mixtures. The impact of biasing effects on complex

modulus (norm and phase angle) values obtained during tests is estimated. Six mixtures were

produced with three distinct base bitumens, including both modified and unmodified binders,

and with varying contents of Reclaimed Asphalt Pavement (RAP), from 0% to 40%. Strain-

controlled tension/compression tests were conducted on cylindrical samples according to a

procedure specifically developed at the ENTPE, called ALFABET (Advanced Laboratory

Fatigue And Biasing Effects Test). The test procedure is composed of an initial series of short

complex modulus tests at varying temperatures and strain amplitudes, followed by five partial

fatigue tests. After each fatigue period, a 24 hour rest period is observed, during which short

complex modulus tests are performed in order to monitor recovery of mechanical properties.

Surface and internal temperatures of samples are constantly monitored throughout the test.

Biasing effects were isolated and quantitatively estimated. The influence of non-linearity,

self-heating and thixotropy on norm of complex modulus and phase angle of bituminous

mixtures was evaluated, both in absolute and relative terms, with respect to initial values

obtained in undamaged conditions.


Influence of moisture on thermomechanical behaviour of bituminous mixtures

used for railway trackbeds

ID: 141

Ramirez Cardona, Diego1, 2

, Di Benedetto, Hervé2, Sauzéat, Cédric

2, Calon, Nicolas

1,

Robinet, Alain1

1 Direction of Engineering, SNCF, La Plaine Saint-Denis, France

2 Laboratory of Civil Engineering and Building (LGCB) & Laboratory of Tribology and

System Dynamics (LTDS) (UMR CNRS 5513), University of Lyon / ENTPE, Vaulx en

Velin, France


The influence of moisture on the thermomechanical properties of bituminous mixtures used

for railway trackbeds is addressed in this paper. The use of asphalt base course materials has

been identified as a suitable structural solution for the further development of both high-speed

and conventional railways, notably in terms of circulation speed and axle load increases.

Moreover, field experiences attest a reduction of the maintenance needs by using asphalt

concrete in the railway platform. Nevertheless, the available in-situ feedback is not sufficient

for observing the long-term degradation of the bituminous layers in railway trackbeds. The

evolution of the thermomechanical properties of bituminous mixtures needs then to be

characterized for the specific railway working conditions (loading, frequency and

environmental exposure). For this, improved 3D tension-compression tests were performed on

mixtures used in railway trackbed. The tests are performed on laboratory-compacted

cylindrical asphalt specimens submitted to sinusoidal loading. A moisture conditioning

procedure was defined and used to simulate the exposure of the materials to weather

conditions. The thermomechanical performances of the materials are compared for the

conditioned and non-conditioned states. A multi-parameter analysis allowed determining the

effect of moisture exposure on the materials behaviour. The results allowed establishing

selection criteria, based on moisture susceptibility and long-term degradation, for bituminous

mixtures to be used in railway trackbeds.


Evaluation of rutting of asphalt concrete pavement under field-like conditions

ID: 167

Said, Safwat Fadhil1, Ahmed, Abubeker Worake

1, Carlsson, Håkan

1

1 Pavement Engineering, VTI, Linköping, Sweden


Permanent deformation, or flow rutting, in bituminous layers is a regular distress mode in

flexible pavements that is manifested as an excessive deformation of bituminous material

along the wheel paths. Rutting gradually increases with repeated loading from heavy traffic.

The asphalt concrete layer’s low shear resistance and inadequate compaction during

construction may have a significant impact on rut formation. A reasonable interpretation of

vehicle loading is however crucial in prediction of rut formation in flexible pavement surfaces

using mechanical pavement design approaches. The interpretation of traffic data regarding

axle load, single or dual wheels, tyre-pavement contact stresses, vehicle speed and lateral

wander have a significant effect on the accuracy of rut prediction. The objective of this study

is to evaluate the resistance of asphalt mixes and the influence of traffic loading on rut

prediction using a linear viscoelastic approach called PEDRO (PErmanent Deformation for

ROads) for predicting both the compressibility and shear deformation of asphalt layers under

field-like conditions. The results indicate that the adopted procedure is effective for a

reasonable evaluation of bituminous mixtures and rut development, as well as to quantify the

influence of vehicle variables on rut formation.


Categories for stiffness and fatigue based on cyclic indirect tensile tests and

their applicability in construction contracts

ID: 173

Mollenhauer, Konrad1, Plachkova-Dzhurova, Plamena

2

1 Engineering and maintenance of Road Infrastructure, University of Kassel, Kassel, Germany

2 Institute of Highway and Railroad Engineering, Karlsruhe Institute of Technology,

Karlsruhe, Germany


The cyclic indirect tensile test (CIT-CY) was recently introduced as additional test procedure

to European standardized asphalt test procedures. In Germany the pavement design can be

based on material characteristics obtained on stiffness modulus and fatigue functions which

are evaluated with CIT-CY. In order to adopt the rules provided by European construction

products directive for these performance-based material properties, categories were

introduced to the product standards which will allow the definition of requirements on these

important characteristics. Based on material properties obtained during various research and

practical pavement construction projects, categories could be defined which allow the

classification of these asphalt mixtures regarding properties which were applied in pavement

design calculations. In order to check the applicability of these categories in construction

contracts, former research projects where evaluated regarding the effect of systematically

varied asphalt properties on the resulting stiffness and fatigue properties. In addition to this,

asphalt mixtures were sampled as loose asphalt mix after industrial production, cored from the

completed pavements and also mixed in laboratory with using the constituent materials.

Based on the found variability in the performance properties a concept for the contractual

implementation of requirements for stiffness and fatigue is proposed.


About the influence of several boundary conditions to results of the cyclic

compression test

ID: 179

Milch, Julian1, Plachkova-Dzhurova, Plamena

1, Hase, Manfred

2, Roos, Ralf

1, Wörner,

Thomas3


Karlsruhe, Germany

2 HNL Ingenieur- und Prüfgesellschaft mbH, Pinneberg, Germany

3 Centre for Building Materials, Technische Universität München, München, Germany


The highly plastic and viscoplastic behavior of asphalt at high service temperatures possibly

leads to irreversible deformations in form of rutting which significantly influence road safety.

Therefore the deformation resistance is one of the most important usage properties of asphalt.

To quantify the deformation resistance, besides wheel tracking, the uniaxial cyclic

compression test as a special case of the triaxial cyclic compression test without lateral

confinement is used in Germany. Thereby cylindrical asphalt specimens are exposed to a

sinusoidal pulsed-shaped cyclic compression load with rest periods for 10.000 load cycles.

The specimens may be fabricated by impact compactor, roller compactor or may be drilled

out of asphalt pavement. As decisive parameter the strain rate at the inflection point of the

pulse creep curve is to be determined. If the inflection point is not reached during the test the

local tangent between the last 1.000 load cycles is considered the strain rate. The deformation

resistance is mostly influenced by asphalt composition (kind of binder, binder content,

granulometry), volumetric parameters as the density and the compression ratio as well as the

kind of compression. Within the project FE 07.0253/2011/ERB it was possible to quantify

and qualify these influences for different pavement layers of 21 test sections. Thereby

precious know-how with cyclic compression test was gained which will lead to a more

detailed description of deformation properties of asphalt.


Additional knowledge of low temperature behavior of asphalt characterized

by maximum indirect tensile strength reserve

ID: 183

Grafmüller, Hedy-Kathlen1, Plachkova-Dzhurova, Plamena

1, Hase, Manfred

2, Roos, Ralf

1,

Wörner, Thomas3


Karlsruhe, Germany

2 HNL Ingenieur- und Prüfgesellschaft mbH, Pinneberg, Germany

3 Centre for Building Materials, Technische Universität München, München, Germany


The maximum indirect tensile strength reserve is currently an important parameter to describe

the low temperature behavior of asphalt. It describes the tensile strength of asphalt in

consideration of traffic loading and cryogenic tension. The combination of Uniaxial Tension

Stress Tests (UTST) and Thermal Stress Retained Specimen Tests (TSRST) is used for

experimental determination of this feature. Specimens can be core samples or specimens

produced in the laboratory. Practice shows that minor deviation in mixtures, even by

complying all tolerances, can have a direct influence on performance-features. In addition to

this the influence on performance-features of mixture production (in laboratory or at mixing

plant) and different production of test specimens (prepared by roller compactor or in situ

compacted cores) are not described sufficiently. The project FE 07.0253/2011/ERB

“Representative Determination of Performance-relevant Asphalt Properties that Provide the

Basis for New Conditions of Contract”, which is in the process of being completed, recorded

and evaluated these influences on low temperature behavior of asphalt. Thereby correlations

between performance-features of mixtures, produced during initial type testing or at a mixing

plant and core samples need to be found. Afterwards it will be possible to indicate the low

temperature behavior of the paved course at the time of initial type testing.


Crack propagation in asphalt mixture based on photoelasticity method

ID: 191

Büchler, Stephan1, Wistuba, Michael P.

1

1 ISBS, Institut für Straßenwesen, Technische Universität Braunschweig, Braunschweig,

Germany


The photoelasticity method is a powerful tool for investigating crack propagation during

laboratory testing of asphalt materials. In this study, a reflection polariscope is used to detect

deformation and cracks on the surface of asphalt mixtures. Six asphalt mixtures commonly

used for base course (AC 22), binder course (AC 16) and surface course (AC 8) layers are

selected. Notched semi-circular bending specimens are produced from these materials to

perform monotonic and fatigue tests. In monotonic tests the specimen is loaded under a

constant strain rate until failure. In fatigue tests, a cyclic load with a frequency of 10 Hz is

applied until failure. Digital cameras are used to record the tests with a rate of 30 images per

second for monotonic tests and 1 image per 2 seconds for cyclic tests. Based on these data,

crack propagation is described in function of time. It is observed, that in monotonic tests a

minimal deformation of the specimen surface occurs while the load is increased and cracking

occurs suddenly at peak load. A similar trend is observed for fatigue tests over a longer period

of time. Again cracking occurs near to the end of the tests.


Modification of binder properties of asphalt from delivery condition to paving

ID: 199

Hase, Manfred1, Schindler, Kerstin

1, Schröter, Anke

1, Zumsande, Kathrin

1

1 Research & development, HNL Ingenieur- und Prüfgesellschaft mbH, Pinneberg, Germany


The determination of binder properties and possible modifications of them during the mixing

process, transport and paving is part of the research project FE 07.0253/2011/ERB

„Representative determination of performance-relevant properties of asphalt as base for new

conditions of contract“. Therefor asphalt (surface, binder and base course asphalt) was

sampled in three phases at 21 highway projects spread over Germany.The first phase

represents the design of asphalt mixture. Initial type testing wih the starting material

(aggregates and binder) were repeated. In addition, the binder was examined in the delivered

condition(directly from the refineries). In the second phase the large scale production of

asphalt will be investigated. For this purpose, asphalt produced at the asphalt mixing plant

was taken during paving. Following in the third phase the paved asphalt course was sampled.

Cores with different diameters were taken at the points where the examined asphalt from the

second phase was paved. Different performance tests were carried out on the extracted binder

of each phase and course. The results of the tests in the dynamic shear rheometer (phase

angle, complex shear modulus (DSR), deformation behavior of binders (MSCR-Test)) and

possible differences between the individual phases and their effects will be explained in this

paper.


The use of hydrated lime in the formulation of asphalt mixtures: European

case studies

ID: 201

Lesueur, Didier1, Denayer, Christophe

2, Ritter, Hans-Josef

3, Kunesch, Christof

4, Gasiorowski,

Slawomir5, d'Alto, Alberto

6

1 NBD Department, Lhoist, Paris, France

2 Carmeuse Group, Seilles, Belgium

3 Federation of German Lime Industry (BVK), Köln, Germany

4 Wopfinger Baustoffindustrie GmbH, Waldegg, Austria

5 Lhoist, Krakow, Poland

6 Unicalce SpA, Lecco, Italy


Hydrated lime is being increasingly used in Europe as a multifunctional additive for asphalt

mixtures. Reasons for this have been thoroughly reviewed and explained in recent years,

showing that the main benefits lie in the improvement in resistance to moisture damage,

slowing-down of bitumen aging and improved mechanical properties. These combined effects

lead to an increased durability of the mixtures. In this paper, examples are given of how these

functionalities are being used in the formulation of asphalt mixtures in several European

countries. Resistance to moisture damage is exemplified in the French and Belgian contexts,

with respectively a case study showing the use of Hydrated Lime modified Asphalt Concrete

(AC) in the severe conditions of continental road mountains (tough winter, curves) and in the

case of Stone Mastic Asphalt (SMA) mixtures. Aging resistance is highlighted in the

framework of German and Polish case studies on AC and SMA mixtures respectively.

Finally, the effect of binder stiffening is explained in the context of Austrian (AC) and Italian

(Porous Asphalt, SMA) examples. These various case studies all concur to the fact that the

use of an active filler such as hydrated lime makes it possible for the formulator to have an

efficient way to adjust asphalt mixtures properties, besides the more usual choices of

aggregate and binder.


Implementing EME2, the French high modulus asphalt in Australia

ID: 204

Petho, Laszlo1, Denneman, Erik

1

1 Pavement Technology, ARRB Group, Brisbane, Australia


Enrobés à Module Elevé Class 2 (EME2) technology was developed in France in the early

1990’s and is now used extensively on main routes, airports and urban roads internationally.

Compared to conventional asphalt bases with unmodified binders, high modulus asphalt is

characterised by a high stiffness, high durability, superior resistance to permanent

deformation and good fatigue resistance. International experience indicates that significant

pavement thickness reductions can be achieved using EME2. Australian road agencies, the

asphalt industry and a research organisation (ARRB)together embarked on a project to

transfer EME technology to Australia. Some of the Australian national bitumen suppliers are

now capable to manufacture and deliver the hard penetration grade binder required in the

production of EME2. As a subsequent step asphalt manufacturers developed EME2 mixes in

France using EN test methods and specification requirements. In order to enable

implementation of the design philosophy in Australia, Austroads and ARRB delivered a

research program on behalf of the Australian state road agencies. The final outcome of the

program is a performance based mix design procedure for EME2, which is based on

Australian test methods and test conditions. Also, a tentative specification framework for

workability, wheel tracking, flexural stiffness, fatigue, and moisture sensitivity were

developed for EME2 mixes, which formed the basis of developing specifications by some

Australian state road agencies. The requirements for manufacturing, paving and compliance

were also provided and validated in a demonstration trial in Queensland, while other trials are

planned in New South Wales and Victoria. The paper describes the development of the

specification framework and provides insight into the research methodology for developing

specification limits. The paper also summarises the design procedure adopted in Australia.

The outcomes are based on extensive performance based laboratory testing which is discussed

in details in the paper. The structural and functional performance monitoring of the completed

trial pavement, including extensive laboratory testing of the plant produced material is also

discussed in the paper. Laboratory and field data collected to date indicates that the EME2

pavement performs as expected.


Influence of hydrated lime on linear viscoelastic properties of mastics

ID: 211

Phan, Cong Viet1, Di Benedetto, Hervé

1, Sauzéat, Cédric

1, Lesueur, Didier

2

1 Laboratoire Génie Civil et bâtiment& LTDS, University of Lyon /ENTPE, Vaulx-en-velin,

France

2 Lhoist Group, Nivelles, Belgium


An ongoing study on influence of hydrated lime on mechanical properties of bituminous

mixtures is carried out in the framework of collaboration between the LHOIST Group and

University of Lyon /ENTPE. In this paper we focus on linear viscoelastic properties of mastic.

Different mastics were produced with the same bitumen penetration grade, same bitumen

content and different hydrated lime content. Hydrated lime replaces a part of limestone filler

(the same mass of removed filler for the same mass of added hydrated lime). Linear

Viscoelastic properties of both produced mastics and bitumen were determined using a

dynamic shear rheometer (DSR). First results and analyses are presented in this paper. The

Time-Temperature Superposition Principle (TTSP) was verified with good approximation.

The 2S2P1D model developed by ENTPE team was used for modelling linear viscoelastic

properties of bitumen and mastics. Effect of hydrated lime is discussed.


Innovative SMA-MA mixture for bridge asphalt pavement

ID: 214

Radziszewski, Piotr1, Sarnowski, Michał

1, Piłat, Jerzy

1, Mieczkowski, Paweł

2, Kowalski,

Karol J.1, Król, Jan B.

1

1 Faculty of Civil Engineering, Warsaw University of Technology, Warsaw, Poland

2 Faculty of Civil Engineering and Architecture, West Pomeranian University of Technology,

Szczecin, Poland


Paper presents innovative technological solution applied in bridge pavement. New asphalt

mixture, called SMA-MA, uses benefits of both mastic asphalt (MA) widely used as a bridge

waterproofing layer and stone mastic asphalt (SMA) and provides more durable mixture.

According to the wide research plan, several mixtures were tested for their resistance to

permanent deformation, water susceptibility, fatigue and aging resistance. Conducted research

proved that such mixture can be successfully used as waterproofing and protective layer as

well as traffic carrying layer. In comparison to the typically used asphalt mixtures (SMA, MA

or asphalt concrete), SMA-MA presents: mixture resistant to permanent deformation with

very low air voids content (about of 0.5%) reachable with typical asphalt mixture compaction

temperature of 180°C. The temperature of application SMA-MA mixture is about 30°C less

than temperature of mastic asphalt, but the ability of sealing is comparable. SMA-MA

mixture is a fast application technology using conventional equipment. In climatic conditions

of middle Europe showing high number of freezing-thawing cycles, it is recommended to use

such innovative technological solution on bridge decks.


New findings in relation to adhesion

ID: 223

Radenberg, Martin1, Nytus, Nina

1, Diedel, Ralf

2, Peuker, Miriam

2, Boetcher, Sabine

1


2 FGK Forschungsinstitut für Anorganische Werkstoffe - Glas/Keramik - GmbH, Höhr-

Grenzhausen, Germany


The adhesion of bitumen and aggregates is a very important factor regarding the durability of

pavements. Loss of adhesion results in extensive renewals. Because of the countries’ and

communes’ low budgets, these should be prevented by the right choice of bitumen and

aggregate. This paper describes the findings of two projects with the goal of quantifying the

main influencing factors on adhesion. Although adhesion is a topic for research since decades,

there still are unsolved questions. The first project examined the component bitumen in detail.

The physical and chemical properties of 90 different bitumen were analyzed and a selection of

15 bitumen, with significant differences in their properties, were used for adhesion tests with

four different aggregates (basalt, rhyolithe, greywacke and diabase). The used test methods

were the rolling-bottle-test, the Munich shake test, the determination of the ITSR and the

contact angle. All test methods led to the fact that there are “good and bad” mixtures of

bitumen and aggregate. The second project analyzes aggregates in detail. The chemical and

mineralogical properties and especially the zeta-potential of eight different aggregates were

determined and four aggregates with significant differences in their zeta-potential (limestone,

greywacke, diabase and quartzite) were chosen for the following adhesion tests with five

different bitumen: rolling-bottle-test, the Munich shake test, a kind of a water-boiling-test,

determination of the contact angle and a new test method using the DSR. The influence of the

zeta-potential (a parameter depending on the pH-value) on the adhesion was proved. The

results of both studies helped to quantify the main influencing factors on adhesion and are

supposed to lead to more durable pavements in the future.


An artificial neural network base prediction model and sensitivity analysis for

marshall mix design

ID: 224

Ozturk, Hande Isik1, Saglik, Ahmet

2, Demir, Birol

2, Gungor, Ahmet Gurkan

2

1 Department of Civil Engineering, Middle East Technical University, Ankara, Turkey

2 Turkish General Directorate of Highways, Ankara , Turkey


This study presents an artificial neural network (ANN) model to predict the Hot Mix Asphalt

(HMA) volumetrics of mixtures prepared by following Marshall mix design procedure. The

input data set of the model is determined to be the aggregate gradation, bulk specific gravity

of aggregates, and binder content of the mixture based on the available data. The proposed

ANN model utilizes one-layer Levenberg-Marquardt backpropagation to predict the

theoretical maximum specific gravity of the loose mixture (Gmm) and the bulk specific

gravity of the compacted mix (Gmb). The ANN was trained using data obtained from

numerous roads with a total of 835 different mix designs. The estimated HMA volumetrics,

Gmb and Gmm, are used to calculate key design criteria such as percent of air voids (Va),

Voids in the Mineral Aggregate (VMA), and Voids Filled with Asphalt (VFA). The results

revealed that the ANN is able to predict volumetrics within a promising accuracy. The

proposed ANN model was able to predict the Va within ±1.0% range 90% of the time and

within ±0.5% range 55% of the time. The reasonable predictions of the model leads to

significant time, cost and labor savings with respect to traditional Marshall Mix Design by

limiting the number of trials to reach to the optimum mix design. With the developed ANN

model, Marshall mix design can take 1.5 to 3 days with little validation effort in the

laboratory. In addition, the model could be used as a practical Quality Control tool for

roadway agencies to verify the mix designs.


Prall tests to study the effect of mortar on the wear of Norwegian asphalt

mixtures

ID: 225

Siebert, Doreen1, Mork, Helge

2

1 Department of Road Technology, Norwegian Public Roads Administration, Trondheim,

Norway

2 Department of Civil and Transport Engineering, Norwegian University of Science and

Technology (NTNU), Trondheim, Norway


With the use of studded tires, the mineralogy of the aggregates used in asphalt mixtures is

considered crucial for the wear resistance of the road surface. High strength of the coarse

aggregates and adequate binder content are usually considered good requirements. However,

field observations indicate that the mortar is the least wear resistant portion of the asphalt

mixture. Being exposed to studded tires, the binder coating the coarse aggregates will be

grinded off, and a significant part of the further wear takes place between the coarse particles.

As the wear is caused by the studded tires, the Prall Test (Method A) is used to check the

effect of the mortar. The purpose was to study how to improve the mortar to achieve both as

little and as even as possible wear on the asphalt surface. In addition, the evenness of the

worn asphalt surface was evaluated by calculating the area which is formed between the peak

and the minimum of the surface texture. Three rock materials with different Nordic abrasion

values were used for the stone skeletons of 19 asphalt mixtures. The mixtures varied thereby

in their combination of rock materials in the fine and coarse aggregates. The paper shows the

results of the Prall Test and the evaluation of the surface texture on the Prall tested specimens.

The correlations of the results to the Nordic abrasion values are opposite of one another,

indicating further research is needed to improve the wear characteristics of the asphalt mixture

and keeping a low noise surface texture at the same time.


Shear strength of hot-mix asphalt and its relation to near-surface pavement

failure – A case study in Southern Brazil

ID: 240

Mattos, João Rodrigo1, Núñez, Washington Peres

1, Ceratti, Jorge Augusto

1, Zíngano, André

1,

Fedrigo, William1

1 Civil Enginering, Federal University of Rio Grande do Sul, Porto Alegre, Brazil


Since the years 1970, several design methods of flexible pavements have considered fatigue

bottom-up cracking as the most critical degradation mechanism. However, in recent times,

premature distresses originated close to the surface of pavements, especially in those with

thick asphalt layers. These distresses are cracks initiating close to the surface and rutting,

which are considered as shear failures. Shear failure close to the pavement surface is a

complex phenomenon caused by factors like: tire-pavement shear stresses, asphalt

characteristics and environmental conditions. In this article, besides discussing theoretical

aspects related, the behavior of asphalt is characterized by shear strength tests and risk

analysis of failure close to the pavement surface. It was found that bitumen modification with

SBS remarkably increases cohesion and, consequently, the asphalt shear strength. While the

shear strength parameters for asphalt with conventional bitumen, at 25°C, are: c = 480 kPa

and angle of internal friction angle(fi) = 46°, the tests on asphalt with SBS modified bitumen,

also at 25°C, resulted in fi = 40°.c = 1,006 kPa and Regarding SBS modified asphalt, the

increase of test temperature from 25°C to 40°c significantly reduces the cohesive interception

from 1,006 kPa to 722 kPa, while the friction angle, which is a function of aggregates internal

friction and interlocking, remains the same (40°). The risk of shear failure near surface of a

pavement consisting of 8.0 cm of SBS modified asphalt; 45.0 cm of crushed rock layers and

60.0 cm of sand was evaluated. The non-uniformity of contact stresses was taken into account

using software EverStress FE. In spite of the structure being safe against shear failure (due to

the SBS modified bitumen high cohesion), it was shown that considering the thermal gradient

on critical shear stresses computations is of paramount importance in the case of overloading.


Moisture damage analysis through the TSR and MIST test using water

conditioning asphalt

ID: 247

Figueroa, Ana Sofía 1, Reyes, Fredy Alberto

2

1 Engineering Faculty, Universidad de la Salle-Colombia, 711, Colombia

2 Engineering Faculty, Javeriana University, 231, Colombia


This paper discusses the results obtained by applying the Moisture Damage analysis to one

asphalt mixture that was designed by the Superpave® method. The characterization of

materials included: rheological, chemical, mechanical and performance tests using eight types

of asphalt whose penetration was 80-100 (1/10mm). One of them was named original, S0, and

the others seven (S3, S6, S9, S12, S15, S18, S21) were water conditioning during 21 months.

Taking in to account that moisture damage is usually determined by the Tensile Strength

Ratio-TSR test, which considers a basic conditioning by temperature and humidity, this

research also performed the Moisture Induced Sensitivity Test-MIST test, including the effect

of water, temperature and pressure applied for the vehicles, which increase the pores pressure

of the mix and could cause some kind of detachment (stripping). The comparison between the

TSR and MIST results showed how important it is to consider the dynamic loads and the

temperature when we need to study Moisture Damage. In addition, it was possible to study

the influence of the water on the asphalt properties and its impact on the rutting of the asphalt

mixture.


Laboratory investigation of asphalt mixture aging

ID: 251

Paul, Dalim Kumar1, Sirin, Okan

1, Kassem, Emad

2

1 Civil and Architectural Engineering, Qatar University, Doha, Qatar

2 Civil Engineering, University of Idaho, Moscow, ID, United States


The rheological properties of asphalt binders change with time. Asphalt mixtures get stiffer

and more prone to fatigue cracking with aging. This study is a part of a comprehensive study

undertaken to develop improved protocol for asphalt mixture conditioning in the laboratory to

simulate asphalt mixture aging due to the climate conditions in the State of Qatar. In this

study, asphalt mixtures were prepared by mixing Gabbro base aggregate with Pen 60-70

binder. Initially, mixtures were conditioned at short-term aging temperature of 135°C for

different time periods (2, 4 and 6 hrs). Long-term aging was completed after compaction of

test specimens to the desired air void level of 7 ± 0.5% by using Superpave gyratory

compactor. Three different long-term aging temperatures (i.e., 75, 85 and 95°C) and four

different aging levels (0, 2, 6, and 10 days) were evaluated in this study. Then, the specimens

were tested in an AMPT to determine dynamic modulus and phase angle. Results of this study

were presented by plotting a series of mastercurves obtained from performance testing of the

aged specimens. The results showed that aging temperature and duration have significant

effects on the viscoelastic properties of asphalt mixtures.


Implementation of EN 12697-49 standard into practice

ID: 285

Dašková, Jaroslava1, Nekulová, Pavla

1, Nekula, Leoš

2

1 Faculty of Civil Engineering, Brno University of Technology, Brno, Czech Republic

2 Měření PVV, Vyškov, Czech Republic


European standard EN 12697-49 “Bituminous mixtures – Test methods for hot mix asphalt –

Part 49: Determination of friction after polishing” describes the laboratory measurement of

surface skid resistance. Measurements can be performed directly on cores taken from asphalt

or concrete roads, or on test specimens prepared in a laboratory. Laboratory test specimens

can be asphalt slabs made in compactors or samples made from splits of various fractions.

Nowadays the results of friction measurement on various types of cores taken from roads are

compared with the results of friction coefficient measured by the TRT dynamic test device.

The goal was to verify the accuracy of laboratory measurement of skid resistance and

determine the relationship between the values of road surface skid resistance and the intensity

of traffic load. So far, the results of friction after polishing were measured using the

Wehner/Schulze test device at the Vienna University of Technology. A new test device

complying to EN 12697-49 was installed in the laboratory of the Faculty of Civil Engineering

at the Brno University of Technology. The results measured using this new device are

compared with those measured in Vienna to harmonize these two devices.


Report on new test method to determine shear properties of asphalt mixtures

ID: 297

Zak, Josef1, Monismith, C.L.

2, Coleri, E.

3, Harvey, J.

4

1 Department of Road Structures, CTU in Prague, Prague, Czech Republic

2 Institute of Transportation Studies, Faculty of Civil and Environmental Engineering,

University of California, Berkeley, Berkeley, United States

3 School of Civil and Construction Engineering, Oregon State University, Corvallis, United

States

4 University of California Pavement Research Center, Department of Civil and Environmental

Engineering, University of California, Davis, Davis, United States


This paper is written as the shortened report of paper version published in the special issue of

Road Materials and Pavement Design Journal for the purpose of presenting the results at the

E&E Congress and thereby inform European audience about achieved outcomes. The focus of

the paper is to present the concept of a newly developed Uniaxial Shear Tester (UST) and

correlations between results from the UST and the Superpave Shear Tester (SST), a tool

broadly recognized for asphalt mix design and rutting susceptibility evaluation. In this study,

the UST testing principles, finite element analysis of stresses, and comparison of measured

data are presented. The correlation was assessed on the basis of two tests, the repeated shear

test and the small amplitude oscillation test also referred as the shear frequency sweep test. It

was shown that the material characteristics determined from UST and SST are highly

correlated. The dependencies are discussed in the sense of linear correlation, correlation

coefficients adn coefficients of variation.


The contribution of asphalt mastic to shear resistance

ID: 305

White, Greg1

1 Fulton Hogan, Brisbane, Australia


An Australian airport was to be resurfaced by asphalt overlay. The airport had experienced

variable performance from similarly designed asphalt overlays in the past. Previous

investigations had established that changes in the asphalt mastic had likely led to a lack of

asphalt shear stress resistance. Various sources of fine aggregate and binder had been used in

previous resurfacing works. Mastic combinations containing two specific fine aggregates

sources and two specific binder sources resulted in variable asphalt performance. The two fine

aggregates were similar except that one contained predominantly Hisingerite clay minerals,

which had potentially detrimental properties. The two binder sources were the same grade of

acid-modified bitumen manufactured from different crude oil source blends with significantly

different properties. A combination of repeated shear stress testing of mastic and bitumen

determined that both the fine aggregate and binder sources significantly affected the mastic

response to shear stress, and therefore expected asphalt shear resistance. No adverse impact

associated with the Hisingerite-rich fine aggregate was found. The two sources of bitumen

showed significantly different properties. It was concluded that apparently similar fine

aggregate and binder sources could have significant impact on mastic, and therefore asphalt,

performance in high shear stress states during hot temperatures. It is recommended that the

current Australian specifications for airport asphalt should be reviewed to prevent

significantly different surface performance from nominally identical and compliant mastic

constituents.


Boat transport and quality of hot mix asphalt

ID: 307

Snilsberg, Brynhild1, Hoven, Bjørn

1, Telle, Roar

2


2 Veiteknisk Institutt, Oslo, Norway


The R&D program “Durable Roads” (2011-2014), was a 4-year research program conducted

by the Norwegian Public Roads Administration (NPRA). The overall objective was to

increase service life and reduce annual costs for the Norwegian road network. One of the

activities in the R&D program has been to study the quality of hot mix asphalt (HMA)

transported by boat and suggest new recommendations for asphalt transport by boat. Norway

is a long and narrow country, with several fjords and long distance between cities, especially

in the northern region. The country has a coast line of 25 000 km, and lies between latitudes

57° and 81° N, and longitudes 4° and 32° E. 7 million tons of HMA was produced in 2014,

and about 2 million tons (30 %) was transported by boat. It often takes up to 24 hours to load

the asphalt on to the boat, transport it by the boat, unloaded it on to trucks and pave depending

on the distance. Because of this the asphalt can in many cases become cold during the

transport and segregation can occur, and the quality of the asphalt pavement can be poor.

There are several actions which may be taken to prevent this cooling and segregation of the

HMA, for instance with use of IR-scanning and specifications for handling. The NPRA has

made a study on this and the findings of this study are presented in this paper.


Automatic installation "UONDA 14-20" to determine deformation, stress and

fracture of materials

ID: 318

Pecheny , Boris1

1 SKF BGTU see Schuchow W/B/, Stavropol, Russian Federation


ns We have developed automatic installation UONDA 14-20, which allows to determine in an

automatic mode indicator on 15 properties of composite materi-als (asphalt concrete, cement

concrete, mortar, etc.) at tempera-tures range from -70 to +70 ° C for three test specimens

schemes. Scheme I – while cooling, heating or maintaining isothermal restra-ined by corners

sample and determine the following parameters: 1) struc-tural shrinkage stress σs, thermal

shrinkage stresses σt or shared structural thermal stresses σst; 2) temperature of the cracking

of the structural and/or thermal shrinkage stress Тc and the ultimate strength of these stresses

Rt, 3) period of thermal stress rela-xation mt.. Scheme ΙΙ - by mechanical uniaxial tension and

determine the follo-wing parameters 4) stress in uniaxial tension σр and tensile strength Rр;

5) the strain in uniaxial tension ξр; 6) a module of elasticity E; 7) a compressive frac-ture A.

Scheme III - while cooling or heating of the sample and lying freely define the following

parameters: 8) coefficient of linear thermal expan-sion of λ; 9) structural transition

temperature (Тс glass transition , fluidity Тт , etc.); 10) linear structural shrinkage ξ у; The

installation consists of a test machine, refrigerating or an electric boxes, remote measurement

and recording temperature efforts and deformations. Eight samples were tested, 30 cm long

with a cross section of 5 by 5 cm at cooling - heating the sample from 0,53 °C/min or less and

at deformation rates of the sample from 0.034 till 49 mm/min for mechanical testing .

Automatic installation of UONDA 14-20 allows to test of samples of ma-terials as in the

initial condition and after aging. Moreover, the aging of the sam-ples can be made at certain

modes directly in a thermostatic camera installation and samples aged under different

conditions, including operational. Installing UONDA 14-20 favorably determined by number

of indicators, accuracy tests, ease in construction and maintenance of the well-known machine

CRT-APTTC, used for study the crack on asphalt samples by the method of AASHTO TP10

and EN12697-46.


Performance evaluation of fly ash asphalt pavement

ID: 321

Ünal, Emine Nazan 1, Epsileli, Sefer Ercan

2, Demir, Birol

1

1 Research and Development Department, General Directorate of Highways, Ankara, Turkey

2 Research and Development Division, General Directorate of Highways 5.Regional

Directorate, Mersin, Turkey


This investigation was carried out to study the effect of fly ash on the field performance of

asphalt pavement. Fly ash was used in stone mastic asphalt (SMA) during the construction of

the wearing course of Gaziantep Ring Road. This SMA is the first application using fly ash in

our country. The performance properties (rut depth and roughness and cracking in the

pavement) were determined. In this research the inertial profilometer with camera has been

used to measure rut depth, roughness and cracking of the road in 5th Regional Division of

Highways of Turkey. As a result of this study, surface performance properties have been

determined. Additional data will continue to be collected and analyzed during the next years.

Performance models will be developed.


Cold bituminous emulsion mixtures - laboratory mix design, trial section job

site and monitoring

ID: 327

Suda, Jan1, Valentin, Jan

1, Žák, Josef

1




Presently the road construction engineering focuses on technologies, which allow reducing

energy demand of the structures to be built. This is closely linked to cutting the release of

CO2 emissions and at the same time to the effort reducing costs for new structures or for

rehabilitation works. Cold emulsified asphalt mixtures are a kind of road building material

which is defined by using specific type of binder and ambient mixing temperatures. Typical is

that their cohesion in the early stage after paving is rather lower and increases gradually

during the curing period. Specific properties of these mixes support their use mainly for low-

volume roads. These mixes have longer tradition in France and partly in the UK. In the Czech

Republic very limited laboratory and practical experience are available for these mixtures.

Until recent time there were even no technical specifications giving rules for design and use

of these cold mixtures. This paper presents laboratory methodology which was used for cold

emulsified asphalt mix design and describes results from such design. Additionally long-term

assessment of experimentally evaluated characteristics is included as well. Since the real

behavior of such mix in pavement structure cannot be with sufficient credibility described by

laboratory tests a trial section was realized in 2014. This should bring additional verification

of the experimental findings. For the trial section a low volume road was selected where

existing pavement dimensions were known and data about daily average traffic were

available. Reconstruction was expected with subsequent monitoring of the new structure with

respect to traffic and climatic effects. The trial section was divided into 6 subsections with 5

different options of pavement design to evaluate effects of designed cold bituminous emulsion

mixes in wearing and binder course. The mixes were designed in some of the options with 30

% of reclaimed asphalt (RAP). Experience from the first trial section in the Czech Republic

and data of site monitoring are presented in this paper.


MINERAL FILLER INFLUENCE ON MASTIC FRACTURE ENERGY

ID: 329

Bardini, Vivian Silveira dos Santos1, Fernandes Júnior, José Leomar

2, Roque, Reynaldo

3,

Klinsky, Luis Miguel Gutiérrez4

1 Environmental Engineering, Universidade Estadual Paulista, São José dos Campos, Brazil

2 Universidade de São Paulo, São Carlos, Brazil

3 University of Florida, Gainesville, United States

4 Centro de Pequisas Rodoviárias - CCR, Santa Isabel, Brazil


The mechanical properties of asphalt mastic influence significantly the overall performance of

hot mix asphalt. The behavior of the asphalt mastic influence almost every aspect of the

design, construction, and performance of hot mix asphalt. The fatigue damage and fracture in

the hot mix asphalt are strongly related to binder characteristics, filler properties, interaction

between the binder and filler, and is a phenomenon affected by the development and growth

of microcracks in the mastic. The mixture performance can be improved if the mastic is

design to resist fracture and fatigue. Fracture energy is an important property related to fatigue

resistance of binders and have a strong influence on the cracking performance of flexible

pavement. A new binder fracture energy test was developed by Roque et al (2012) based on

nonlinear 3-D Finite Element Analysis (FEA) to determination of stress and strain on the

fracture plane, which in turn assures accurate determination of fracture energy. The study of

the mastic behavior is important to evaluate the effects of the mineral filler amount and the

asphalt binder properties, as well as the different filler types and nature effects, and evaluate

its influence on the asphalt binder stiffness and elasticity, provided by the filler addition at

different ratio filler/binder. The overall objective of this study was to determine the fatigue

damage characteristics of asphalt binders and mastics by measuring the fracture energy. The

addition of filler to the asphalt binder decrease the fracture energy value, compared to the

pure asphalt binder, and as the filler amount increases, the fracture energy value decrease

even more, including the Portland cement filler.


Uncertainty assessment of standard tests of bituminous mixtures

ID: 335

Barral, Marisol1, Calvo, Carmen

2, Miranda, Lucía

3, Jiménez, Rafael

4, Barceló, Francisco

José3, Loma, Javier

5, Hidalgo, Mª Elena

6, Tamayo, Santiago

7, Gómez, Andrés

8, Berbis, José

9,

García, Carlos10

, Guillén, Rafael11

, Carmona, Marisa12

, García, Antonio13

, Subarroca, Mar14

1 R&D, Campezo, San Sebastian, Spain

2 Laboratory, Junta de Castilla y León, Valladolid, Spain

3 R&D, Repsol, Mostoles, Spain

4 Transport Laboratory, CEDEX, El Goloso, Spain

5 Laboratory, Asfalto y Construcciones Elsan, Madrid, Spain

6 Technical Department, Eiffage Infraestructuras, Madrid, Spain

7 Laboratory, Diputación de Alava, Vitoria, Spain

8 Laboratory, BECSA, Castellón, Spain

9 Technical Department, Pavasal, Valencia, Spain

10 Technical Department, Collosa, Valladolid, Spain

11 Technical Department, Sacyr, Madrid, Spain

12 Laboratory, Intromac, Cáceres, Spain

13 Laboratory, CEPSA, Alcalá de Henares, Spain

14 Technical Department, Sorigué, Lleida, Spain


Characterization of any material requires the existence of test methods to quantify with the

greatest reliability properties in the scope of the analysis. In the body of EN standards of

asphalt mixtures, there is a section where the precision values shows repeatability and

reproducibility of the test method. Test methods variability is usually based on interlaboratory

exercises. However this section is not always completed, or the detailed data come from

limited experiences or that do not correspond exactly to the method described in the standard.

Information provided about the accuracy of the method should be considered very relevant.

This study is based on a work developed by Aleas (Group of Spanish Laboratories Associated

to Asefma), a set of organizations specialized in the production and characterization of asphalt

mixtures. Its aim is to evaluate the accuracy described in the test method “EN 12697-12 water

sensitivity of bituminous mixtures”, according to Method A, through a round robin test. In

this EN standard, paragraph regarding accuracy indicates that the precision data have not been

established, and there is a reference regarding similar indirect tensile tests. In this paper it is

estimated the precision of the test for two types of bituminous mixtures: BBTM type B and

AC, through a round robin test which involved 15 laboratories. Final results are compared

with those of the reference published in the EN standard. This study has also used to calculate

an overall estimate of its uncertainty using a methodology developed within the working

group ALEAS.


UGR-FACT test in the study of fatigue and cracking phenomena in asphalt

pavements

ID: 341

Moreno-Navarro, Fernando1, Rubio-Gámez, Mª Carmen

1

1 Ingeniería de la Construcción y Proyectos de Ingeniería, Universidad de Granada, Granada,

Spain


The understanding of fatigue and cracking phenomena is crucial to design more durable

asphalt pavements. For this purpose UGR-Fact test has been recently developed. This paper

describes this test method that consists of a device that is able to simulate traffic loading and

climatic stresses in asphalt pavement at laboratory scale. The asphalt material is performed

through a controlled fatigue cracking process that allows the analysis of the cracking

propagation in the initiation, progression and failure stages. Among its main advantages to

highlight: the test can be carried out in stress or strain controlled mode, it allows the study of

laboratory specimens and also cores from pavements, multi-layers section can be analysed, it

is easy to reproduce at a low economic cost. On the other hand the use of dissipated energy

concepts in material fatigue processes establishes a series of parameters that accurately define

the fatigue cracking performance of a bituminous mix


Adjusting design air void Levels in Superpave mixtures to enhance durability

ID: 348

Huber, Gerald1, Haddock, John

2, Wielinski, Jason

1, Kriech, Anthony

1, Hekmatfar, Ali

2

1 Heritage Research Group, Indianapolis, United States

2 Purdue University, West Lafayette, United States


When developed in the early 1990s the Superpave method of asphalt design was structured

similar to the Marshall method of asphalt design. In the Marshall method asphalt was

designed with 3 to 5% air voids (typically 4%). Compaction specifications typically left the

mixture with 8% air voids on the road. It was reasoned that traffic would compact the asphalt

mixtures and achieve an ultimate density of 96%, the same as the design. Superpave calls for

a design air void content of 4.0% (no range) and compaction specifications allow the mixture

to have 7 to 8% air voids. Subsequent research in the early 2000s showed that after traffic

densification air voids stabilize at about 6%. This paper discusses proposed changes

Superpave asphalt design method to design at 5% air voids. Target air voids after compaction

would be the same, 5%. To achieve compaction of 95% (5% air voids) requires changes to the

laboratory compactive effort in the Superpave design method. The concept of designing and

compacting asphalt at 5% air voids is inspired by the LCPC method of asphalt design used in

France. The perceived benefit to Superpave is an improvement in mixture durability expected

from lower air permeability leading to a reduced rate of oxidative hardening. This paper

discusses the concept of setting air void levels in asphalt design, research to identify changes

to the Superpave method and recommendations for design compactive effort to be used.


Asphalt mixes properties and pavement structure mechanics

ID: 352

Cápayová, Silvia1, Gschwendt, Ivan

1, Zuzulová, Andrea

1

1 Department of Transportation Engineering, Faculty of Civil Engineering, Slovak University

of Technology in Bratislava, Bratislava, Slovakia


A. The review of deformation characteristics and properties of asphalt mixes for road

pavement construction. In addition review of changing and development in properties of

asphalt binder and asphalt mixes (e.g. modification). Some results from the laboratory tests of

asphalt mixes production with chemical agents (polymers) and additives improving adhesion

to aggregates, enable the mixing procedure under low temperature (WMA). B. The

requirements on asphalt mixes properties and description of laboratory tests. The most

important properties decisive for serviceability and bearing capacity of pavement structures.

Design of asphalt mixes composition, requirements on mixes composition exercised in

Slovakia. Catalogue sheets of asphalt mixes with requirements according traffic load of road,

prepared with empirical approach to composition design. C. Energy consuption on mixes

production for procedure HMA and WMA, comparison. The new low energy asphalt mixes,

energy saving possibilities. Factors and way to protect the environment. D. Pavement design

and calculation of structures with asphalt layers with different quality. Theoretical solution of

multilayer system with imput data as a design values (E, μ, h), not real. Influence of

temperature on stresses and strain distribution in models of pavement structure. Partition the

year on time periods with different layers temperature. Theoretical approach to calculation of

pavement surface permanent deformation. The rut depth as criterium in pavement design.

Discusion : radial strain or radial stress in the bottom of critical pavement layer as criterion.


Influence of the mastics on the permanent deformation of asphalt pavements

ID: 365

Moreno, Emilio1, Contreras, Verónica

1, Carrera, Virginia

1, Palleiro Costa, Lucía

2

1 REPSOL, MADRID, Spain

2 University of Coruña, Coruña, Spain


The resistance to permanent deformation or rutting of asphalt mix depends on many factors;

among them we can mention the type and dosage of bitumen, the aggregate gradation, the

nature of the aggregates, the ambient temperature of the pavement, traffic loads and intensity,

the degree of compaction, etc. In this study the permanent deformation is evaluated based on

a single parameter; the filler/bitumen ratio. The composition of the mastic of a mixture has a

significant influence on certain properties, such as fatigue and permanent deformation. Is

logical to assume that as the ratio f / b increases the elasticity of the mixture decreases and

stiffness increases, bringing its performance against the action of the traffic in terms of rutting

be different. Thus, we have evaluated the characteristics related tothe permanent deformation

of mixtures and mastics varying the ratio f / b. At the same time it has tried to find

relationships between the results of various tests.


Mixing and compacting asphalt mixtures modified with silane molecules

ID: 400

Buechler, Stephan1, Wistuba, Michael P.

1, Cannone Falchetto, Augusto

1

1 Braunschweig Pavement Engineering Centre, Technische Universität Braunschweig,

Braunschweig, Germany


If chemically reactive silane molecules are added to a road asphalt mixture the performance

properties change significantly. The additive coats the surfaces of the aggregate particles and

forms a layer of 1 to 100 nanometres in thickness. Due to this effect, advantageous changes in

asphalt performance behaviour are noticed such as consistent and higher compaction, and a

highly reduction of binder stripping. This paper reports on workability observed during

production of asphalt mixtures of the type AC 11 with 25/55-55 and AC 16 with 50/70

produced in laboratory with and without adding silane molecules. During mixing and

compaction the power consumption was continuously recorded. During the mixing process it

was stated, that if silane molecules were added, the time needed for coating the aggregate was

reduced by 20%, while the power consumption of the mixing unit always remained at the

same level. When temperature was reduced stepwise during the compaction process, from the

standard mixing temperature of 135 to 95 degree Celsius for the AC 16 mixture, and of 145 to

105 degree Celsius for the AC 11 mixture respectively, compactability always remains at the

same level. From this laboratory study it was concluded, that workability may be significantly

improved through a silane additive.


Permanent deformation of hot mix asphalt under compression and tension

ID: 401

Isailović, Ivan1, Wistuba, Michael P.

1, Augusto, Cannone Falchetto

1

1 Braunschweig Pavement Engineering Centre, Technische Universität Braunschweig,

Braunschweig, Germany


In this paper, the existence of a correlation between the permanent deformations measured

under different stress conditions is investigated. The results from cyclic penetration test,

which is performed under compressive loading, are compared with the experimental values

obtained with the indirect tensile fatigue test, which presents a dominant tensile stress field.

Four different asphalt mixtures for surface and base layers were prepared and tested with both

tests. The results indicate a significantly different material behavior between the two testing

methods. In the case of the cyclic penetration test a first material densification is followed by

deformation associated to shear effects with no change in material properties. On the other

hand, during indirect tensile fatigue tests, a progressive accumulation of permanent

deformation is linked to a continuous change in the mechanical properties of the material. It is

observed that the development of permanent deformation under compression does not

correlate with the deformation accumulation due to a tensile stress state. This suggests that the

experimental results obtained with indirect tensile fatigue test cannot be used to predict the

permanent deformation properties of asphalt mixture layers under the compressive state of

stress induced by traffic load.


THE DEVELOPMENT OF A SOUTH AFRICAN HIGH STIFFNESS

ASPHALT USING FRENCH EME METHODOLOGY

ID: 407

Fremont, Sonia1, Lawrence, David

1, Strickland, David

2, Hornsey, Bob

3

1 Shell Bitumen European Solution Centre, Illkirch-Graffenstaden, France

2 Shell Bitumen, Manchester, United Kingdom

3 Shell Bitumen, Durban, South Africa


For a considerable period of time, a type of asphalt mixture called high modulus mix (EME,

Enrobé à Module Elevé) has become very popular in France in the construction of major

roads and highways. EME, as a high modulus asphalt mixture, contains a very stiff binder that

can be as hard as a 10/20pen. To ensure that the asphalt mix has good performance and

durability, a mixture design is carried out and the performance properties, including

compactability, water sensitivity, resistance to rutting, stiffness modulus and fatigue are

measured and specifications in terms of stiffness and fatigue have to be met for EME

qualification. Therefore, high modulus mixtures combine high binder content, good aggregate

quality, high mastic content and low void content and the high stiffness is achieved with the

use of a hard grade of bitumen. As EME’s contain such a hard grade of bitumen, the

manufacturing temperature is higher than standard asphalt products, C.approximately 180

This paper describes how the high modulus mix has been developed, meeting the South

African HIMA and French EME 2 specifications with aggregates, reclaimed asphalt product

(RAP) and a 10/20pen grade bitumen that has been manufactured and supplied from a

refinery in South Africa. The paper discusses the binder and asphalt mix properties that are

obtained and compares these properties to a typical French EME.


Fatigue characterization of Enrobés à Module Elevé with high RAP

percentages

ID: 410

Mohan, Salil1, Naus, Robbert

1

1 Dura Vermeer Infrastructuur BV, Hoofddorp, Netherlands


To address the increasing traffic on Dutch highways, the application of high modulus asphalt

mixtures such as EME, has proven to be an excellent concept. The use of a relative low pen

binder combined with an increased binder content results in a mixture with improved

stiffness, fatigue and rutting properties. In structural pavement design analysis, the improved

properties result in a thinner total required asphalt thickness while maintaining the same

lifetime expectancy compared to an conventional asphalt mixture. As part for further

improving this concept, a laboratory study was carried out to develop an understanding of the

effect of different RAP percentages on mixture performance. Displacement controlled fatigue

tests were performed at two strain levels using a four – point bending test setup. In this study

one type of EME was examined containing RAP percentages of 0, 30, 50 and 70%.

Additional to fatigue testing, stiffness measurements were also performed. Results from

fatigue tests were analyzed using the widely used phenomenological method and a more

fundamental approach based on dissipated energy concepts. Results from both methods were

used in an mechanistic – empirical design environment to calculate minimum required asphalt

thicknesses for a chosen situation. In terms of mechanical behaviour, preliminary results

indicate that the addition of RAP results in marginal differences between the studied mixtures.

The paper reports of the different steps and motivation behind choices. Laboratory findings

are discussed and compared with existing models enabling an progress in rational pavement

design.


Improvements regarding the procedure of rutting prediction of asphalt

pavements

ID: 416

Dragon, Ines1, Reinhart, Uwe

2

1 Materialprüfungsanstalt, EUROVIA Services mbH, Ottendorf-Okrilla, Germany

2 Institut für Stadtbauwesen und Straßenbau, Technische Universität Dresden, Dresden,

Germany


In terms of the verification to the fatigue of asphalt pavements by using the method of the

RDO Asphalt 09 a lot of experiences could be gained. These experiences were used to

advance the technical regulations. On the other side the valuation of the deformation behavior

of asphalt pavements is currently based on the assessment of the rutting on the basis of

deviatoric equiva-lent stresses. With this procedure only comparative assessments of different

designs and materials can be made. So the plastic deformation properties of the materials are

not considered. Furthermore, no information of the temporal plastic deformation behavior of

the construction, as well as the depth of the ruts at a specific time of usage can be made. In

recent years there have been made some improvements to the method of the prediction of

rutting. Now all load conditions were used, which are taken into account in the dimensioning

process. For the different stress conditions triaxial or uniaxial cyclic compression tests on slim

specimens were made to determine material-dependent impulse creep curves and then they

were described based on a model. In this paper, the statistical material model of the

deformation behavior and the improvements regarding the procedure of the prediction of

rutting are explained and results of calculations are presented.


EFFECTS OF AGGREGATE-ADDITIVE COMBINATIONS AND

GRADATION PROPERTIES FOR ASPHALT MIXTURE STRIPPING

ID: 418

İskender, Erol 1, Aksoy, Atakan

2, Sayin, Aytuna

3, Erdöl, Berna

3

1 Civil Engineering Department, Faculty of Technology, Karadeniz Technical University,

Trabzon, Turkey

2 Engineering Faculty, Karadeniz Technical University, Trabzon, Turkey

3 Tenth Regional Directorate, General Directorate of Highways, Antalya, Turkey


The stripping performance of asphalt mixtures was evaluated. Stone Mastic Asphalt (SMA)

mixtures were produced with 19mm and 12.5mm nominal aggregate size and two gradations

were also chosen for each nominal aggregate size. Coarse-fine-filler materials were selected

as the basalt aggregate in terms of aggregate fractions. Basalt filler material was replaced with

limestone filler and the filler effect was investigated. 1%-1.5%-2% hydrated lime contents

were selected for each mixture combination and the hydrated lime effects were evaluated. The

AASHTO T283 test method was studied. Moisture damage decreased with limestone filler

replacement substituted for basalt filler. Mixtures that included basalt filler showed the

highest moisture damage ratio for 1.5% hydrated lime incorporation but mixtures with

limestone filler gave the highest damage ratio at the 1% percentage. For both basalt and

limestone mixtures the moisture damage ratio increased with the translation from 19mm to

12.5mm for coarser and finer gradations separately.


7. Smart, Intelligent and cost effective roads

Reliability in pavement design

ID: 33

Dalla Valle, Paola1, Thom, Nick

2

1 Arup, Solihull, United Kingdom

2 NTEC, University of Nottingham, Nottingham, United Kingdom

Topic: 7. Smart, Intelligent and cost effective roads

This research presents a methodology that accounts for variability of the main pavement

design input variables (asphalt modulus and thickness, subgrade modulus) and uncertainties

due to lack-of-fit of the design models and assesses effects on pavement performance.

Variability is described by statistical terms such as mean and standard deviation and by its

probability density distribution. The subject of reliability in pavement design has pushed

many highway organisations around the world to review their design methodologies, mainly

empirical, to move towards mechanistic-empirical (M-E) analysis and design which provide

the tools for the designer to evaluate the effect of variations in materials on pavement

performance. This research has reinforced this need for considering the variability of design

parameters in the design procedure and to conceive a pavement system in a probabilistic way.

This study only considered flexible pavements. The sites considered for the analysis, all in the

UK, were mainly motorways or major trunk roads. Pavement survey data analysed were for

Lane 1, the most heavily trafficked lane. Sections 1km long were considered wherever

possible. Statistical characterisation of the variation of layer thickness, asphalt stiffness and

subgrade stiffness is addressed. A model is then proposed which represents an improvement

on the Method of Equivalent Thickness for the rapid and repeated calculation of performance

life for flexible pavements. The output is a statistical assessment of the estimated pavement

performance. Rather than the single deterministic result that would be derived by considering

average values of input variables, a range of values and probabilities is found for any

particular outcome. The proposed model to calculate the fatigue and deformation lives is very

fast and simple, can be included in a spreadsheet, and is well suited to use in a pavement

management system where stresses and strains must be calculated millions of times. The

research shows that the probability distributions of the performance lives follow a lognormal

distribution. The coefficient of variation of all sites considered varies from a minimum of

45% to a maximum of 227% for the fatigue life and from a minimum of 39% to a maximum

of 315% for the deformation life.


New opportunities in performance based contracts

ID: 63

Moenielal, Mahesh1, de Vries, Ewoud

1

1 Ballast Nedam, Nieuwegein, Netherlands


In the Netherlands clients were used to define fixed specifications for road works. The

requirements are shifting into functional specifications where the contractor is free to design

and select materials provided that the pavement construction is able to bear the traffic loads

for the design period. Only the asphalt top layer is specified by acoustic properties. Clients

validate the process with verifications instead of supervision at site. Because the contractor is

now responsible for the long term maintenance, 20 to 25 years instead of the standard periods

(5,7 or 10 years) a higher quality level has to be reached. Thus, the contractor is triggered to

design in terms of life-cycle because too much maintenance leads to high lane rental costs.

There is more opportunity for design optimizations which reduces costs and/or lead to less

risks in the life-cycle. However, too large discrepancies in the as-built situation leads to

unexpected maintenance which results in high lane rental costs. This causes the need for new

measuring methods and control systems. Expert knowledge is therefore required. The

pavement consultant was used to have a minor role and was often characterized as Gyro

Gearloose. Nowadays comparison with Steven Spielberg suits more. The pavement consultant

has a greater role in the DBFM-contract and is more challenged on his skills. The consultant

is not only involved in the calculation of the pavement construction, but also with the

verification of design specifications, optimization of the geometrical design, converting

system requirements into specifications for construction and above all predict the impact of

shortcomings in construction on the maintenance of the pavement construction. The new role

of the pavement consultant will be demonstrated with experiences of the DBFM-contract "the

widening of motorway A15 Maasvlakte-Vaanplein", the most heavy-duty motorway in the

Netherlands.


The effect of new tyre type, tyre pressure and axle configurations of heavy

trucks on asphalt pavement lifetime

ID: 92

Varin, Petri1, Saarenketo, Timo

1

1 Roadscanners Oy, Rovaniemi, Finland


There has been an increasing trend in the transportation industries of the Nordic countries

over the last decade towards a move to longer and heavier trucks and heavier axle

configurations. In Finland in 2013 the allowable total weights and dimensions of heavy trucks

were raised from 60 tonnes to 76 tonnes. In Sweden the maximum total weight of trucks will

rise to 74 tonnes and in Norway 60 tonnes trucks will be permitted on main roads. In order to

assess this trend in Finland the Finnish Transport Agency established a “Weights and

Dimensions” project to determine the present condition of the Finnish road network and

estimate the effect of new heavier trucks on road loading resistance and lifetime. Outside the

Nordic countries other countries will also face the effects of rapidly increasing numbers of

super single tyres and higher tyre pressures over the next few years, even those where the

total truck weights or axle weights are not being raised. To assess this the ROADEX Network

partners commissioned a prestudy project on "The effect of axle and tyre configurations on

pavement durability". The aim of the prestudy was to produce a general information package

on the effects of different truck options, axle configurations, tyre types and tyre pressure

options on pavement structures. This included modelling stresses and strains within the

pavement and performing calculations of residual pavement lifetimes for typical pavement

structures used in the ROADEX Network area The paper will present the key results of the

two projects mentioned above and present some recommendations how pavement

management policy should be changed to meet the future challenges.


Measurement and analysis of homogeneity in asphalt pavements

ID: 124

Espe, Erik1, Bakløkk, Leif Jørgen

2

1 Viatech as, Kongsberg, Norway

2 TMT - Trondheim, Norwegian Road Authorities, Trondheim, Norway


This paper describes a new and innovative measurement method, which uses laser scanning to

determine the homogeneity of asphalt pavements. The term “homogeneity of asphalt” is used

in this paper to describe the even-ness of texture and surface characteristics (sub-centimeter)

of the asphalt surface. The homogeneity of the new-laid compacted asphalt pavements is very

important in order to secure a satisfactory lifetime of the pavement. This is particularly

important where low temperature or coarse asphalt materials are used. It is also important for

the usage characteristics of the road, notably the friction level presented to normal car tires.

As of today, contractors have no measurement method of determining the required

homogeneity of the new-laid surface, but have to rely on expertise and knowledge of the

paving crew. In addition, the road authorities have no objective means of approving or

rejecting the new-laid pavements. The current laser scanner system operated by the

Norwegian Public Road Administration is extended with the described method in order to

measure homogeneity of the asphalt surface. The main advantage of this method is the

possibility to measure a complete 4m width in one single run at normal driving speeds. Thus,

the cost and risk of measuring the surface is optimized. This paper describes the advanced

analysis software use in this method, and how innovative signal processing is used to extract

the most important parameters from the measurement data.


PEHKO Project 2015-2025, increasing the productivity of paved road

management in Finland

ID: 144

Tapio, Raimo1, Lehtinen, Jukka

2, Ylinampa, Jaakko

2, Saarenketo, Timo

3

1 Finnish Transport Agency, Helsinki, Finland

2 Central Finland Centre for Economic Development, Transport and the Environment,

Jyväskylä, Finland

3 Roadscanners Oy, Rovaniemi, Finland


The decline in national budgets for paved roads in Finland has been causing increasing

deterioration rates on the Finnish paved road network that will soon lead to major problems

on the network. To counter this concern the Finnish Transport Agency has started to put

emphasis on new methods and policies that could address the problem. Two 10 year R&D

pilot projects will commence in 2015 in the areas of Lapland and Central Finland. Their

ambitious goal will be to cut down the annual paving costs in the areas by 40-50% from the

current levels. The basic idea and goal for the PEHKO project will be to improve the practices

and policies in paved road maintenance and management. Its aim will be to enhance the

productivity of funding investments and improve the condition of the paved road network, or

at least keep at the current level with less resources. This goal will be achieved by focusing on

three targets: 1) Improving the daily drainage maintenance standards for paved roads. This

will lead to increased pavement life times and lower annual paving costs. 2) Applying new

NDT (non destructive testing) road survey technologies in the diagnostics of paved roads

allowing to engineers to their focus rehabilitation measures exactly on the problem sections

and address the roots of the problems rather than just treating the symptoms. 3) Changing

maintenance policies from reactive to proactive maintenance. This will mean that

maintenance crews will fix the potential problem sections before serious pavement damages

appear. This presentation will present in detail the goals, polices and techniques that will be

used in the project.


Lastrada - process capability KPIs for the quality assurance of aggregates and

asphalt

ID: 185

Albrecht, Robert1, Jung, Konrad

1, Lange, Geir

2, Christiansen, Espen

2

1 Dr. Jung & Partner AG / LASTRADA, Berlin, Germany

2 Veidekke Industri AS, Oslo, Norway


How to efficiently manage the quality of a natural product under the assumption of changing

properties, changing sources, a complex production process, environmental influences and a

high throughput of bulk production? Is it possible to predict the next non-conformity event?

In this paper we describe how to run a QC system in an effective and (at the same time)

understandable and easy way. We show how to make use of Key Performance Indicator

(KPIs) on the basis of process capability indices in aggregate and asphalt quality control.

Hence, given a tool for the management to pinpoint where resources are needed and action

has to be taken in order to secure QC according to requirement/EN-standards. In doing so, we

describe several aspects of the LASTRADA approach: the definition of meaningful Key

Performance Indices, the advantages of a central database solution and standardised

workflows when it comes to maintaining a suitable data basis and finally, the challenge to

simplify the complexity in the presentation of data. We will provide a number of up to date,

practice-proven examples on how process-related issues can be detected. The paper ends with

some illustrative examples from a company using this system. The examples clearly show

how processes can be improved using KPIs on responsibility levels closer to the production

process, i.e. on site manager level.


Smartvia concept : a 5 years feedback on standalone pavement structure

monitoring

ID: 202

Pouteau, Bertrand1, Berrada, Kamal

1, Drouadaine, Ivan

1

1 Research Center, Eurovia Management, MERIGNAC, France


During the last decade, we notice changes in paving technologies, such as the use of RAP,

warm mixes. To design these innovative technologies, engineers first used laboratory and

modeling ressources. Then field experiments are required. Gathering feedback from onsite

experiment is a real challenge. Since 2010, Eurovia Research Center developed the Smartvia

concept to support onsite feedback for innovative pavement products. This concept is based

on the use of sensors fully integrated to the pavement structure during road works,

programmable electronics with real time data acquisition software. This enable to trigger

acquisition on demand or on event and to push the data through wireless networks towards

specific data servers. This paper provide a 5 years feedback on standalone pavement structure

monitoring based on 6 experimental jobsites. We describe two specific projects: a one scale

experiment on the impact of trenches on the durability of pavement (performed in partnership

with Lille Metropole Communauté Urbaine) and the Novatherm demonstrator that enable

deicing of road surface using geothermal energy. The authors focus on sensors selection

(temperature, humidity, pressure, strain), their integration to the structure, their durability and

data management. A vision of future challenges towards a real smart and intelligent road will

be discussed.


On laser scanning, pavement surface roughness and international roughness

index in highway construction

ID: 294

Zak, Josef1

1 Department of Road Structures, CTU in Prague, Prague, Czech Republic


The paper reports data from the research project where the objective was to develop and

validate a tool that would be publicly available and would leverage the point cloud data

commonly acquired on sites to calculate the pavement surface properties such as the

International Roughness Index and Roughness. To do so, a unique RIRI program was written

in Python to streamline the point cloud data analysis. The program is publicly available under

the GNU General Public License. Further, the paper presents data from three test sections

where the developed methodology was used to calculate the pavement smoothness properties

from a point cloud and compared to classical, reference, methodologies, such as the rod and

level and precise levelling. The paper focuses on the variability and precision of all

methodologies. It was found that the Pearson type IV distribution is a fitting descriptor for

histograms calculated with the help of Freedman and Diaconis’s law from rectified slopes and

roughness values with regard to its fitness and use of its parameters for the pavement surface

smoothness description.


Light Coloured Asphalt

ID: 409

Naus, Robbert1, Voskuilen, Jan

2

1 Dura Vermeer Infrastructuur BV, Hoofddorp, Netherlands

2 Ministry of Infrastructure and the Environment, Rijkswaterstaat, Utrecht, Netherlands


In the Netherlands many roads are illuminated in the evening and at night. Both inside and

outside urban areas and from bicycle paths to motorways. This public lighting consumes a

tremendous amount of energy, which also means considerable CO2-emissions. Dura Vermeer

has developed Luminumpave, a light coloured asphalt to reduce public lighting. The

maximum effect is obtained by using a light coloured stone, an almost colourless synthetic

binder (clear binder) and white pigment. The lighter colour also has an effect on road safety

and on the thermal properties of the asphalt pavement As part of an innovation cooperation

with Rijkswaterstaat in September 2011 on motorway A35 a test section is laid. A reference

section with the top layer of standard two-layer porous asphalt (PA 8) and three variants

Luminumpave were realised (PA 8 with black bitumen, and PA 8 and SMA 11 with clear

binder) with a total length of 625 meters. The purpose of this test section was to investigate

the suitability as a wearing course on motorways and the quantification of the effect on the

public lighting. The studies and measurements have focused on: the civil engineering

properties to assess the applicability; the light reflection properties in order to determine the

reduction in public lighting. From the civil engineering research it can be concluded that

Luminumpave is suitable for use on motorways. The reflection of sunlight causes lower

temperatures in the asphalt pavement and as a result less rutting is expected. The lighting

research has shown that a reduction of the public lighting of more than 40% is possible. This

means huge energy savings and associated reduction in CO2-emissions. Also on unlit roads a

light coloured surface seems to be very interesting. The visibility of a light coloured road

surface is much better than that of a standard (dark coloured) road surface.


Strategy Management and Maintenance for Thin Surface Course Systems

ID: 421

Khojinian, Arash1, Parry, Tony

1, Thom, Nicholas

1

1 Nottingham Transportation Engineering Centre, Faculty of Engineering, The University of

Nottingham, Nottingham, United Kingdom


Thin surface course systems (TSCS) have been in widespread use on the Highways England

Strategic Road Network since their introduction in the 1990s. A premature failure of TSCS

will result in early intervention and hence a significant cost. Surface disintegration (fretting) is

acknowledged to be the main defect within TSCS. It occurs when individual aggregate

particles under the action of traffic and environmental factors are lost. The aim of this

research was to study and seek to set up a series of recommendations to improve the

management and maintenance strategy of thin surface course systems for their entire

serviceable life. This research was planning to explore and investigate the long term

performance of thin surfacing systems in particular in relation to surface disintegration

(fretting) on site. As part of this research TSCS core samples were obtained from several

sites. The cores were subjected to a comprehensive matrix of laboratory tests for determining

the rheological behaviour characteristics of binders. This included Penetration grade,

Softening Point determination and Sweep test using a Dynamic Shear Rheometer over a range

of different temperatures (5oC to 80oC) and frequencies (0.1Hz to 10Hz) tests. A set of

laboratory tests for evaluating the mechanical performance characteristics of the mixtures

were also carried out to fully investigate the effect of compaction on the long term

performance of the mixtures. The resulting mixtures’ properties were then investigated by

looking at their compaction results including Bulk Density, Max density and air void Content.

The laboratory data was then interpreted and analysed against available in-situ performance

data in order to find any possible correlation between the in-situ performance surface of TSCS

(in particular fretting) and binder/mixture properties of Thin Surface Course Systems.


8. Sustainable development

Low rolling resistance pavements in Denmark

ID: 71

Pettinari, Matteo1, Lund-Jensen, Bjarne Bo

2, Schmidt, Bjarne

1

1 Danish Road Directorate, Hedehusene, Denmark

2 NCC Roads A/S, Vejen, Denmark

Topic: 8. Sustainable development

Low rolling resistance pavements can reduce fuel consumption by 4%.In Denmark the CO2

emission from the road transport alone is estimated to 4,6 mill ton pr. year. Implementing low

rolling resistance pavement on the entire 4000 km of state roads in Denmark will provide a

reduction in CO2 emission by 160.000 tons pr. year and saving the road users by 64 million

litre of fuel. Approximately one fourth of the total energy consumption in Denmark is

consumed by the road transport, a consumption that is continuously growing. About one third

of the energy consumption from the road transport comes from overcoming rolling resistance

between the tire and road. In 2011 Danish national funding gave the possibility to initiate the

COOEE project, CO2 emission reduction by exploitation of rolling resistance modelling of

pavements. The project involved two universities, Roskilde University and the Technical

University of Denmark, the Scandinavian contractor NCC roads and the Danish Road

Directorate. The challenge was to develop a road pavements with low rolling resistance that

still provide other functionalities as friction to support traffic safety and low noise emissions.

In Denmark three tests sections has been constructed between 2012 and 2014 – the paper

presents the experience from construction these pavements as well as the obtained

functionalities such as rolling resistance, skid resistance and evenness.


Life cycle of bitumen: ageing-regeneration-ageing

ID: 75

Sá-da-Costa, Margarida1, Diogo, António Correia

2, Farcas, Fabienne

3

1 Materials Department, National Laboratory of Civil Engineering (LNEC), Lisbon, Portugal

2 Chemical Engineering Department, Instituto Superior Técnico, University of Lisbon,

Lisbon, Portugal

3 Materials Department, Institut Français des Sciences et Technologies des Transport , de

l'Aménagement et des Réseaux (IFSTTAR), Paris, France


Asphalt recycling is nowadays a requirement that accounts for demands on sustainability and

energy efficiency. Despite being a minor component, the bitumen binder plays an important

role in asphalt performance and also contributes for pavement deterioration. During its full

lifetime bitumen faces different aging processes, mainly due to interactions with environment,

which involve changes in chemical composition, in structure and microstructure and, by

consequence, changes in rheological behavior (rheological material functions and material

constants). From the perspective of bitumen regeneration, there are some relevant aspects

like: (1) To what extent is it possible revert the ageing of bitumen? (2) To what extent can

regeneration processes restore original bitumen properties? (3) What kind of response can we

expect from regenerated bitumen when facing a new ageing cycle? There is no single answer

to these questions, since several factors are to be considered such as the degree of ageing of

bitumen in RAP (Reclaimed Asphalt Pavement), the RAP content and the properties of the

new binder added to RAP. The methodology used to evaluate bitumen properties is behind

those answer, since it provides the tools for understanding the phenomena that are taking

place. The [ageing-regeneration-ageing] life cycle of bitumen used in Portuguese road

construction was evaluated following a methodology based on chemical, structural and

rheological characterization. Chemical analysis included the follow up of generic fractions

(SARA, saturates+aromatics+ resins+asphaltenes) at different stages of the ageing and

regeneration processes, as well as the pursuit of oxidation by infrared spectroscopic index.

Structure and microstructure were assessed by using gel permeation chromatography (under

extreme conditions) and atomic force microscopy. Furthermore, a rheological characterization

was done, by measuring the relevant material functions in different regimes (dynamic and

permanent (steady)).


Sustainable urban roads

ID: 83

Guisado Mateo, Francisco1, Díaz Martín, Patricia

2, Botella, Ramón

3, Ramirez Rodriguez,

Antonio2, Moreno Martín, Emilio

1, Miró Recasens, Rodrigo

3

1 Technology Center Asphalt and Specialities, Repsol, Mostoles, Spain

2 R&D, Sacyr Construcción, Madrid, Spain

3 Technical University of Catalonia UPC-BarcelonaTech, Barcelona, Spain


In recent years, within the current growing awareness and tightening of the environmental

regulations, it has been attempting to correct the impacts that the manufacture and application

of Asphalt Mixtures causes on the environment. The concept of sustainability has come to the

field of bituminous mixtures with three main components: reducing costs, reducing emissions

and reducing consumption of raw materials, preserving resources for the future.

Rehabilitation and Maintenance activities of road pavements generate an increasing amount of

waste from the milling of the damaged layers of bituminous mixtures. This material, which

has a high cost and its properties are exceptional, should be reused in manufacturing new

mixtures of the same type and function. We are more obliged to provide solutions that will

minimize the consumption of natural resources by using a new generation of Bituminous

Mixtures. This paper presents the efforts carried out to develop a technology for the

construction, maintenance and rehabilitation of roads based on the use of Half-Warm Mix

Asphalt, with a recovery rate up to 100% that applies low temperatures at the production (90-

100 ºC) and compaction (70-80ºC) stages of road/street construction. These mixtures will

contribute to improve the sustainability of urban areas by reusing materials of high quality,

reduction in energy consumption and reduction in GHG emissions with a hefty lower impact

on the environment.


Service life considerations based on asphalt analysis

ID: 111

Lipke, Sebastian1, Lipke, Petra

1

1 Federal Highway Research Institute, Bergisch Gadbach, Germany


Especially in Germany in the future road construction will be shaped less by the new

construction but rather through the maintenance and renewal, because the existing road

substance is used up in growing ever stronger and quicker measure. With reference to the

steadily rising traffic load and for a qualified maintenance planning the knowledge of the real

structural condition of an asphalt pavement gets more and more important. The present paper

presents an approach that forecasts the remaining service life of an asphalt pavement at any

point of time on the basis of asphalt parameters determined by laboratory tests. Therefore

asphalt samples were taken from existing asphalt pavements which had already taken many

years of traffic load and their specific asphalt properties such as stiffness and fatigue

resistance were determined by laboratory tests. With these results of the asphalt studies

together with a forecasting method based on the analytical design of asphalt pavements a

possibility exists to give statements to the expected remaining service life of asphalt

pavements. To optimise this approach of forecasting the remaining service life case studies

were carried out. In these the whole asphalt structure of the asphalt pavements were examined

at different points of service life.


Facilitating the adoption of sustainable technologies in the asphalt sector

ID: 133

Wayman, Matthew1, De Visscher, Joëlle

2, Maeck, Johan

2, Bueche, Nicolas

3, Anastasio, Sara

4,

Peeling, James1, Vansteenkiste, Stefan

2, Vanelstraete, Ann

2, Schobinger, Bastien

3, Hoff,

Inge4


2 Asphalt Pavements, other Bituminous Applications and Chemistry, BRRC, Brussels,

Belgium

3 Laboratoire des voies de circulation LAVOC, Ecole polytechnique fédérale de Lausanne,

Lausanne, Switzerland

4 Department of Civil and Transport Engineering, Norwegian University of Science and

Technology, Trondheim, Norway


A need exists to bridge the gap between innovation in the bituminous materials sector and

adoption of the new technologies by national road administrations (NRAs). The Evaluation

and Decision process for Greener Asphalt Roads (EDGAR) enables NRAs to do this by

providing an assessment methodology which makes sustainability information on new

technologies readily accessible to the decision-making process, and therefore facilitates quick

adoption of the technologies that offer the greatest sustainability benefits for the highways

sector and society as a whole. EDGAR commenced with a wide-ranging review of the range

of ‘green’ technologies in the bituminous materials sector and the sustainability benefits that

they offer. Two methodologies to assist NRAs were then devised. The first acknowledged that

the ability to recycle asphalt is its foremost environmental attribute, and devised a quick,

qualitative method for the assessment of recyclability. The second devised a methodology for

a more detailed assessment of the sustainability of any bituminous technology, considering all

three facets of sustainability: environmental, social and economic, with particular attention

given to how the information might be used in the decision process by NRAs, and the

common challenges they might encounter when assessing a ‘novel’ technology.


How do we improve the durability of porous asphalt?

ID: 147

Jacobson, Torbjoern1, Sandberg, Ulf

2, Viman, Leif

2

1 Swedish Transport Administration, Sunbyberg (Stockholm), Sweden

2 The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden


How do we improve the durability of porous asphalt? Authors: Torbjörn Jacobson, Swedish

Transport Administration and Ulf Sandberg, The Swedish National Road and Transport

Research Institute (VTI) Porous asphalt (PA) laid in one or two layers has a long tradition in

Sweden. The aim initially was to improve road safety and traffic flow during rain. Over time,

the focus has shifted to noise reduction and today PA is used primarily as a measure to limit

noise pollution. Early on it was noted that PA had a shorter lifetime than dense asphalt

because of inferior durability. In order to improve the durability of PA laid in two layers a

research project started in 2010. Three major test roads were laid in different regions of

Sweden. Noise reduction was 7-8 dB(A) when new and reduced by 0.5-1 dB(A) per year. The

wear resistance of these PA has been acceptable with minimal raveling and other damage. A

few results and features of the test roads: • Drainage is improved by increased cross slope and

improved drainage at the roadsides. • A new binder – highly modified bitumen with good

adhesion and elasticity. • Mix design: high binder content (≥ 6.3 %), high void content (≥ 23

% by volume), high stone content (85 %) and suitable additives. • Aggregates with good

adhesion to bitumen and with good resistance to studded tyres were used. • If raveling

tendencies are observed, the road may be sealed with a low content of Fog Seal emulsion.


Practical verification of the theory behind long-life asphalt pavements

ID: 152

Bateman, Damien1, Carswell, Ian

1, Caudwell, Louise

2, James, Donna

3, Ferne, Brian

1, Meitei,

Bobby1, Jones, Colin

1


2 Highways England, Sheffield, United Kingdom

3 Highways England, Guildford, United Kingdom


Traditional asphalt pavement design is based on a mechanistic–empirical approach which

identifies the strain at critical locations in the pavement structure to safeguard the road against

fatigue and structural deformation. However, research has shown that when roads are well

built above a certain threshold, structural damage is non-existent with rutting confined to the

surfacing, an ideal and economic design solution. The existence of these ‘long-life’

pavements challenges the current design and maintenance methodologies and suggests a need

for a radical approach to pavement design. Although findings from global research have

verified that a threshold effect for pavements does exist, there is limited real life data to

support this theory. This paper, sponsored by Highways England, aims to demonstrate the

threshold effect as well as develop a radical approach to flexible pavement design and

maintenance, using the threshold concept. Three instrumented road sections of varying

thicknesses were designed, built, and trafficked under varying wheel loads and speed. The

results demonstrated classical pavement deterioration through both rutting and fatigue

cracking. However, one of the sections showed no deterioration and the associated strains

illustrate the threshold effect. In addition, a methodology is presented which involves the

development of a robust model that predicts tensile asphalt strains directly from falling weight

deflectometer (FWD) measurements which could be used as a tool to identify long life

pavements on the English Strategic Road Network (SRN).


Design of bituminous pavements in Austria - a mechanistic approach

ID: 172

Eberhardsteiner, Lukas1, Marchart, Bettina

1, Blab, Ronald

1

1 Institute of Transportation, Vienna University of Technology, Vienna, Austria


The objective of pavement design is to develop pavement constructions, which are able to

resist appearing traffic loads and climatic conditions during the intended life time. The

concerning regulations and standards in Austria are based on semi-analytical models to

describe the mechanical response to these loads. As, thereby, standard constructions are

derived for 7 load classes and 8 pavement types, neither actual data concerning traffic load,

nor performance related material characteristics like stiffness or fatigue behavior of the hot

mix asphalt (HMA) used can be considered leading to significant design reserves. Hence, a

mechanistic design approach for bituminous pavements in Austria was developed, recently,

and is expected to be released as a new national standard. Thereby, statistically derived model

parameters or actually measured input parameters (traffic loads, HMA stiffness behavior,

HMA fatigue behavior) or a combination of both are taken into account. The possible

consideration of the advantages in mechanical behavior of modern bituminous mixtures not

only allows more economic design results but also leads to the efficient use of bitumen, a

crude oil product with decreasing availability.


Perpetual pavement design and construction using anti-fatigue base layer on

expressway S8 in Poland

ID: 175

Ruttmar, Igor1, Grajewska, Agata

1, Pełczyńska, Karolina

1

1 TPA Sp. z o.o., Pruszków, Poland


Within the frame of realisation of express way S8 close to Warsaw in formula “Design &

Build” the Contractor decided to design alternative pavement structure based on principle of

perpetual pavement using anti-fatigue base layer. The construction started in 2014. The

authors present the design assumptions and methodology based on French design method,

short analysis of different conceptions for asphalt mixtures for anti-fatigue base course and

high-modulus base and binder course together with test results. The pavement was designed

for 50 years traffic load with assumption that no serious structural heavy maintenance will be

required, except regular renewal of wearing course. The results of life cycle cost showing the

benefits for public Investor comparing to traditional pavement structure is also presented.


Calculation of energy and carbon dioxide on asphalt pavements

ID: 180

Martinsson, Kristina1, Jacobson, Torbjorn

2, Lundberg, Roger

3

1 Swedish Transport Administration, Orebro, Sweden

2 Swedish Transport Administration, Solna, Sweden

3 NCC Roads AB, Umea, Sweden


This contribution describes an LCA tool (EKA, Energy and Carbon Dioxide in asphalt

production), which was developed by the Swedish Transport Administration for calculating

the energy and CO₂ emissions during manufacture and laying of asphalt. In addition to

describing the various steps in the production of asphalt from "farm to table" EKA can also be

used in the development of environmentally friendly asphalt pavements. EKA is an aid in

selecting pavement, binders, aggregates and additives. It can also be used for review and

improvement of processes in asphalt production and laying. The goal of the EKA is to

increase the use of energy-efficient pavements while maintaining performance and quality.

Calculations with EKA shows that the production of binders and manufacture of asphalt are

the processes that require the most energy and generates the most CO2. When reclaimed

asphalt is mixed into asphalt mixes, if temperature is reduced or if surface dressing is used it

reduces energy as well as CO₂ emissions are reduced, sometimes they can be halved. By

comparing different pavement types we have formulated a strategy for the maintenance

program. The summary over the last year’s production shows that the average of energy and

carbon dioxide per square meter has been reduced.


Long term performance of a highly modified asphalt pavement and

application to perpetual pavement design

ID: 212

Kluttz, Robert Q.1, Dongré, Raj

2, Powell, R. Buzz

3, Willis, J. Richard

3, Timm, David H.

4

1 Kraton Polymers, Houston, TX, United States

2 Dongre Laboratory Services, Inc, Fairfax, VA, United States

3 National Center for Asphalt Technology, Opelika, AL, United States

4 Auburn University, Auburn, AL, United States


This paper reports on the final surface characterization and full forensic analysis of a highly

modified asphalt pavement versus conventional Hot Mix Asphalt (HMA) at the National

Center for Asphalt Technology (NCAT). The highly modified asphalt pavement is 20%

thinner than a series of companion sections. The sections were subjected to 20 million

Equivalent Single Axle Loads (ESALs) over a period of 5 years. At the end of two full track

cycles, the thinner highly modified section has outperformed the others in permanent

deformation and bottom up fatigue cracking. Modeling results give quite reasonable

agreement with observed performance. The performance results validate pavement modeling

reported at the International Conference on Perpetual Pavements (ICPP) in October and

demonstrate that substantial thickness reduction is possible while retaining and even

improving long term performance. Equally important, material properties of highly modified

mixes may be used to adjust the damage model calibration factors in the AASHTOWare/r/

Pavement ME Design software so that appropriate pavement thickness can be determined

through rational design. This methodology has been put into practice and so far the

performance results on commercial projects have validated the design predictions.


Climate change impact compared to life cycle assessment results: a pilot case

in Flanders

ID: 308

Anthonissen, Joke1, Van den bergh, Wim

1, Braet, Johan

2

1 Faculty of Applied Engineering Sciences, University of Antwerp, Antwerp, Belgium

2 Faculty of Applied Economic Sciences, University of Antwerp, Antwerp, Belgium


In 2013, a pilot project ‘Carbon Free-Ways’ was elaborated in which the Flemish government

included both price and CO2 emissions as award criterion in a public tender for the

reconstruction of a field case in Kontich (Belgium). The road works include the construction

of a base course with 50% reclaimed asphalt pavement and a surface course with 100% virgin

split mastic asphalt, both are warm asphalt mixtures. Data was measured during the execution

of the works for raw materials, transport and asphalt production. This real live data is used for

all calculations. The approach used in the pilot project (Carbon Counter tool) to assess the

emissions from the road construction is compared to a comprehensive environmental analysis

following the life cycle assessment methodology. This paper aims to answer the following

four main research questions. What is the difference between the results from the Carbon

Counter and the life cycle assessment calculation? What is the contribution of climate change

impact to the total single score environmental impact? Which materials or processes have the

highest environmental impact? What is the environmental impact of processes which are

beyond the scope of the pilot project? It was found from the current study that CO2 emissions

or climate change impact is for sure not the only important environmental impact. Fossil

depletion was found to majorly contribute to the total single score impact and transport by

lorry and the raw material bitumen are processes and materials with an important contribution

to the environmental impact.


Lessons learned in developing an environmental product declaration program

for the asphalt industry in North America

ID: 323

Mukherjee, Amlan1, Dylla, Heather

2, Willis, Richard

3

1 Civil & Environmental Engineering, Michigan Technological University, Houghton, United

States

2 Engineering, National Asphalt Pavement Association, Lanham, MD, United States

3 National Center for Asphalt Technology, Auburn, AL, United States


The objective of this paper is to report the technical and organizational challenges involved in

the development of the North American Environmental Product Declaration program for

asphalt mixtures. The paper explores how differences in stakeholder priorities and

perspectives, in the pavement construction industry, directly shape the Product Category

Rules (PCR) defining the program. The paper draws attention to specific Life Cycle

Assessment (LCA) related technical questions and highlights how the solutions are

negotiated. The primary challenge identified is how to ensure technical rigor of the underlying

LCA, while recognizing the interests of the stakeholders and ensuring the delivery of a

program that is effective. The paper discusses how technical issues regarding system

boundary choice, data use and allocation presented challenges for the PCR Development

Working Group accounting for different stakeholder interests. It is very important to note that

this paper does not discuss the PCR itself, but rather provides insights into the discussions that

informed the PCR development.


Development of an incremental method for mechanistic asphalt concrete

pavement deterioration models

ID: 355

Ramadan, Eiad1, Beckedahl, Hartmut J.

1

1 Department of Civil Engineering, University of Wuppertal , Pavement Research Centre,

Wuppertal, Germany


There exist considerable discrepancies between laboratory and analytical investigation and

field performance studies for different modes of deterioration of asphalt pavements. When

laboratory determined distress parameters are compared with corresponding field data, the

predictions are poor. There are several reasons why this approach has not been as successful

as hoped for. One reason is the change in the property of asphalt concrete over time. This is

caused by the combined effects of the traffic and the environment. The reasons for the

property change of asphalt concrete may be due to a change in air voids, aging of asphalt,

seepage of moisture, or a combination of all these effects. As these changes occur over time,

the engineering properties of asphalt concrete mixtures also change. To gain considerable

confidence on pavement performance modelling and to bring it more closely to the pavement

performance seen in the field, a rational design methodology is required. This methodology

should take into account the evolution of pavement performance throughout its life time. One

obvious choice is the use of incremental method for developing asphalt pavement

deterioration models. The incremental method for the analytical prediction of asphalt

pavement deterioration will consist of an integrated set of models, which will be able to

predict the progression of deterioration for each mode of distress. The accumulated damage

for each deterioration mechanism can be calculated in increments as a function of time and/or

damage. The increment spacing will be a function of material property variation caused by

climate, time, and/or traffic. Thus the pavement service life is divided into several increments

and the calculation input data (material properties, climate, traffic, surface profiles, and layer

thickness) as well as the pavement damage will be changed with each new increment. The

priority research objective is the creation and validation of a new incremental method for

mechanistic asphalt concrete pavement deterioration models to account for variation in

pavement material property and the consequent pavement structural response. The secondary

objectives are to modify existing or to develop new analytical pavement performance models.


New developed software tool for assessment and calculation of emissions for

different asphalt pavement rehabilitation methods

ID: 359

Snížek, Václav1, Valentin, Jan

1, Engels, Michael

2



2 Wirtgen GmbH, Windhagen, Germany


Construction industry similarly to any other industry, is forced to face recent trends and

necessary environmentally friendly solutions, like for example emphasizing emission

reduction. On the other hand, modern methods, especially coming from the IT sector, are

often not easy adoptable for this industrial area. As part of ongoing research activities started

within the European CoRePaSol project and continuously followed in Centre for Effective

and Sustainable Transport Infrastructure in the Czech Republic to focus was oriented on the

issue of energy demand and emission production calculation for pavement recycling

techniques. Together with these assessments a new software tool was developed, which is in

detail oriented on the determination of environmental burden in terms of emissions if different

pavement rehabilitation techniques are used. There were already lots of studies on greenhouse

gas emissions presented, but most of them focus mainly on CO2, not reflecting other

emissions. The importance of this paper is in the detailed identification and understanding and

description of other greenhouse gas emissions like NOx, HC, CO, fine particles matter and

also CO2. The study contains an application of the assessment software (calculator) for a real

job site, presenting possible pavement rehabilitation methods including their technological

variants and a subsequent decision for a preferred solution. Included are traditional

rehabilitation methods (mill&fill, including RAP material with different portion) as well as

both cold and hot in-place recycling techniques. This paper aims to show the truth of

environmental impact of available rehabilitation methods, as well as to present the developed

software application.


Analysis of a heat exchanging asphalt layer using a finite element approach

ID: 361

Vuye, Cedric1, Guldentops, Gert

2, Rahbar, Nima

2, Nejad, Alireza Mahdavi

2, Van den bergh,

Wim1

1 Faculty of Applied Engineering, University of Antwerp, Antwerp, Belgium

2 Civil and Environmental Engineering, Worcester Polytechnic Institute, Worcester, United

States


Current aims regarding environmental protection, like reduction of fossil fuel consumption

and greenhouse gas emissions, require the development of new technologies. These new

technologies should enable the production of renewable energy which is both cleaner and

cheaper. This necessity encourages engineers to develop new ways to capture energy for later

use. In this paper, the use of a heat exchanging asphalt layer (HEAL), as a means to extract

low temperature heat, is studied in detail. Such a system, which harvests heat energy by

flowing water through a heat exchanger embedded in the pavement structure, could definitely

have a significant thermal energy output since pavement materials absorb large amounts of

solar insolation. The focus in this paper is on asphalt concrete pavements since these absorb

the largest amount of solar insolation and will benefit the most from the removal of heat in the

form of an increase in lifetime. The main objective is to study the energy output and

efficiency of the HEAL. In order to achieve this, a parametric study on different thermal

properties of the asphalt pavement has been performed using a validated Finite Element (FE)

model of the collector. It is shown that both the absorptivity and thermal conductivity have a

large influence on the outlet temperature and solar efficiency. Using this FE model it will be

possible to predict the long-term energy output of the HEAL taking into account all

geometrical, material and weather parameters.


Life+ Sustaineuroroad software

ID: 391

Cavagnol, Ismail1

1 Technical Affairs Department, USIRF, Paris, France


The French voluntary commitment agreement (CEV) which gathers the whole road sector, so

public as private allowed to engage more the road industry in an environmental process by

fixing objectives to reach on several standards such as the natural resource conservation or

reduction of greenhouse gas emissions. The objective in a general way was to increase the

environmental performance of companies by making always better technically while

contributing to the conservation of the environment. This is the way in 2010, the USIRF

launched the SEVE software, which is 4 years later become the reference regarding

environmental analysis of the road sites. After this success, USIRF wanted to gather the

European Road Profession (ASEFMA, COLAS Hungary, EUROVIA Germany, ERF and

CG33 (General Council of Gironde)) to build a new software inspired from SEVE named

SustainEuroRoad in the frame of the European Environmental project LIFE+. This software

will be able to drastically reduce the environmental impact of road construction and

maintenance in Europe. The principal objectives of this project is to reduce the energy

consumption, including fossil fuel and natural resources and to reduce GHG emissions linked

to road building and maintaining processes and to the preservation of natural resources. By

providing a unique tool to decrease the road industry environmental impact by keeping the

same technical performance or improving it, local authorities will be able to evaluate the

environmental impact between different solutions in the part of adjudication all around the

Europe with the same software. SustainEuroRoad software will increase the integration of

environmental assessment in the selection of road project and incite road sector to generalize

BAT (Best Available Technique) regarding economical, social and environmental aspects. In

order to reach the project objectives, the software will calculate the environmental impact of

road construction and maintenance on 3 indicators: • GHG emission (ton eq. CO2) • Energy

consumption (MJ) • Natural aggregates consumption (ton) The annual environmental situation

of the European road industry evolve in an encouraging way and undoubtedly this kind of

project around which public and private profession had known to meet in a collective way to

mutualize its efforts leads the road profession higher.


TRACC – Road techniques adapted to climate change

ID: 393

Mazars, Arnaud1

1 Cerema (Centre for studies and expertise on Risks, Environment, Mobility, and Urban and

Country Planning), Territorial Division for the South-Western Regions, Toulouse, France


Conventional road techniques lead to use materials transported far from production sites, to

incorporate them in very high temperature asphalt mixtures, and finally to transport them to

road construction sites and to lay them down with specific equipment. In context of climate

change and with the need to minimize the use of natural resources, the TRACC project,

focused on road techniques adapted to climate change, studied all products in regard with

sustainable development and technical aims. Technical evaluation of one hundred products

was done with studying capacities of each to be laid down on various previously defined

deteriorated pavement as the capacities to resolve those troubles. All aspects of sustainable

development were apprehended : • economy integrating direct costs, durability, …, •

environmental balance with ecocalculator simulations (emission of greenhouse gases, energy

consumptions, …) • social approach taking into account workers, residents/users and

operating of infrastructures. Initiated in South West Europe (Spain, Portugal and South West

of France) between infrastructures owners, contractors and public laboratories, this process is

now used, in France, with professional national associations to build a shared database.

Utilization of these data leads to propose to users road techniques resolving their technical

maintenance problems of users in promoting those that are the best relating to sustainable

development. The final aim of TRACC is to demonstrate that this is possible to have

equivalent but alternative maintenance system in using road techniques more correct

regarding environmental, economic and social aspects than conventional products.


DURABROADS - Towards a more durable and resilient road pavement

ID: 424

Diez, Jose1, Castro, Daniel

2, Casado, Raquel

3, Hubrich, Christopher

4, Gaspar, László

5,

Azpeitia, Maider6

1 European Union Road Federation, Brussels, Belgium

2 GITECO Research Group, Cantabria, Spain

3 Acciona Infraestructuras S.A, Madrid, Spain

4 Fraunhofer Institute for manufacturing engineering and automation, Mannheim, Germany

5 KTI Non-profit Ltd, Budapest, Hungary

6 Tecnalia, Miñano, Spain


Nowadays, traditional road materials, procedures and techniques are expected to deliver a

minimum performance but unexpected new challenges have a negative impact reducing their

lifetime. In addition, each kilometre of road requires a large amount of materials and energy

for its construction, maintenance and rehabilitation which are not viable according to new

environmental patterns. Hence, the search of more cost-effective and eco-friendly practices in

the road sector represents a priority for the industry. In this sense, the DURABROADS EU

Project aims at providing a sustainable solution through the design, development and

demonstration of cost-effective, eco-friendly and optimized long-life pavements, more

adapted to freight corridors and climate change through innovative designs and the use of

greener materials improved by nanotechnology. Throughout the Project lifetime, an analysis,

selection and characterization of the most suitable nanomaterials will be carried out to create

different nanotechnology-enhanced binders. Accordingly, various Warm Mix Asphalts

(WMA) will be tested incorporating nanomaterial-modified bituminous binders as well as

Reclaimed Asphalt Pavement (RAP) and by-products. Based on the results of these tests,

better performance pavement sections for different climate conditions and traffic loads will be

constructed on a real case scenario. DURABROADS represents also a formal collaboration in

road infrastructure research between the US Federal Highways Administration and the

European Union. The Project is financed by the EU FP7 scheme. The consortium is composed

of a multi-disciplinary partnership formed by 9 partners including academia, industry, SMEs

and research centers: University of Cantabria, Acciona Infraestructuras S.A., Fraunhofer,

Institute for Transport Science, European Road Federation, Tecnalia Research and

Innovation, Norwegian Graphite, BSRIA and Inzenierbuve Ltd.


Investigation into the stiffness improvement, microstructure and

environmental impact of a novel fast-curing cold bituminous emulsion mixture

ID: 425

Dulaimi, Anmar1, 2

, Al Nageim, Hassan3, Hashim, Khalid

1, 4, Ruddock, Felicite

5, Seton,

Linda6

1 Department of Civil Engineering, Liverpool John Moores University, Liverpool, United

Kingdom

2 Kerbala University, Kerbala, Iraq

3 Liverpool Centre for Materials Technology, Department of Civil Engineering, Liverpool

John Moores University, Liverpool, United Kingdom

4 Babylon University, Babylon, Iraq

5 School of Built Environment, Liverpool John Moores University, Liverpool, United

Kingdom

6 School of Pharmacy and Biomolecular Science, Liverpool John Moores University,

Liverpool, United Kingdom


Cold bituminous emulsion mixtures (CBEMs) have environmental advantages over

conventional hot mix asphalt as they are cold products and are safe to use whilst also reducing

energy. However, their low early strength and long curing time have been cited as the main

barriers for their wide utilisation. This study describes the development of a new fast-curing

CBEM incorporating binary blended cement filler (BBCF) containing high calcium fly ash

(HCFA) and high aluminosilicate waste material (HASW) to replace the commercial

limestone filler. In addition, a waste alkaline NaOH solution was used as a replacement for

the pre-water. The new CBEM needs only ambient temperature curing in order to achieve

strengths comparable to the traditional hot mixture in a very short time (less than one 1 day).

Water sensitivity of the mixtures was assessed by the Stiffness Modulus Ratio (SMR).

Scanning electron microscopy (SEM) was employed to characterise the surface morphologies.

Furthermore, the environmental impact of using these waste materials in CBEMs was

assessed by using a toxicity characteristic leaching procedure (TCLP).The results indicated a

significant improvement in the indirect stiffness modulus (ITSM) test and water sensitivity

compared to hot mix asphalt. Moreover, SEM analysis confirmed the formation of hydration

products after various curing ages. Furthermore, the TCLP test for environmental impact

revealed that the heavy metal concentration in the leachates satisfied the required criteria.


9. Miscellaneous

Anti-vibration pavement: Case of study Novara municipality

ID: 417

Venturini, Loretta1, Giannattasio, Federica

1, Sangalli, Lorenzo

1

1 Iterchimica S.r.l., Suisio, Italy

Topic: 9. Miscellaneous

The phenomenon of vibrations induced by vehicular traffic is due to several factors including

transit speed, irregularity of road surfaces, vehicle mass and type of bituminous conglomerate

used. In fact, the vehicular source enters mechanical energy in the pavement which is

generated either because of the vehicle and because of the road surface inhomogeneity. These

vibrations are instead propagated in function of the constituent materials. Depending on the

new production technologies, such road materials may instead be designed to allow the

attenuation of vibrations that, in this case, arrives reduced to the surrounding buildings,

limiting the disturbance to the inhabitants and the degradation of the Historic Buildings of the

territory. The use of bituminous mixtures containing rubber powder resulting from the

recycling of tires at the end of their life (normally used for the reduction of noise emissions)

allows concretely the reduction of such vibrational impacts, in all urban environments where

vibrations from vehicular traffic, on road or on iron, have a significant impact on human

living comfort. The verification of this solution has been developed on a pavement made for

the Municipality of Novara. The test involved the analysis of the data detected with the

transition vehicle of reference, either on a stretch of anti-vibration pavement, and on one of

reference. The signal has been filtered in different bands, obtaining the corresponding SEL.

The results showed the anti-vibration level reached.


Prioritization for rehabilitation and preventive maintenance of pavement

projects in Texas

ID: 420

Dessouky, Samer1, Papagiannakis, Athanassios

1

1 Department of Civil and Environmental Engineering, University of Texas at San Antonio,

San Antonio, Texas, United States

Topic: 9. Miscellaneous

State highway agencies make decisions on prioritizing rehabilitation (RH) and preventive

maintenance (PM) projects based on data extracted from the Pavement Management

Information System (PMIS). The Texas department of Transportation (TxDOT) uses a

combination of approaches that rely significantly on judgment for identifying PM and RH

projects. Due to finite resources and an extensive road network to maintain, maintenance

engineers must make optimal and cost-effective decisions to prioritize projects to receive

appropriate treatments. Currently, prioritization methods implemented by TxDOT range from

a simple ranking of projects based on judgment to comprehensive optimization by

mathematical programming models. A state-wide survey was developed to obtain the methods

and key factors used by the districts to make project selection decisions. The survey responses

suggested that the major key factors for project selections are; condition score and distress

score, surface age, average daily traffic, number of failures, skid number, ride score and

maintenance expenditures. The survey also suggested that PMIS data combined with visual

inspection are the main tools use to prioritize projects.

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