TYROSAFE

Tyre and Road Surface Optimisation for Skid Resistance and Further Effects

Karen ScharniggBASt (Federal Highway Research Institute)

3rd International Road Surface Friction Conference Safer Road Surfaces – Saving Lives15th – 18th May 2011, Gold Coast (Australia)

Project information

• FP7 Coordination Action• Consortium:

AIT, former: arsenal research (Austria)BASt (Germany), IFSTTAR, former: LCPC (France), RWS-DVS (The Netherlands), TRL (UK), ZAG (Slovenia), FEHRL (Belgium)

• Duration: 2 years (July 2008 – June 2010)• Webpage: http://tyrosafe.fehrl.org

(safety)(energy)(health)

Background

Skid resistanceRolling resistanceNoise emission

©www.wdr.de/themen/wetter/nav/karten/europa.gif

different …

- measuring policies- measuring methods- measured parametersInterdependencies ??

Objectives / Concept

• raise awareness, coordinate and prepare for European harmonisation and optimisation

• of the assessment and management of essential tyre/road interaction parameters

• to increase road safety and support greening of European road transport

Knowledge sharing & awareness raising

Adoption & harmonisation

Identify best

practice(s)

Development of new solutions & technologies

WP

6 M

ana

gem

ent

WP1 Policies of EU countries of skid resistance, rolling resistance

and noise emissions

WP2 Harmonisation of skid-resistance test methods and choice of reference surfaces

WP3 Road surface properties – skid resistance, rolling

resistance, noise emissions

WP4 Environmental effects and impact of climatic change – skid resistance, rolling

resistance, noise emissions

WP5 Dissemination and raising awareness

future influence

Work Packages

WP1: Policies of EU countries of skid resistance, rolling resistance and noise emissions

Topics• Review of ... EU policies and standardisation work Current position in EU member states Differences, advantages/disadvantages of approaches

• Recommendations for future harmonised policies

Pictures provided by CEN/TC227/WG5 and Arsenal Research

Pictures provided by CEN/TC227/WG5 and AIT

WP1: Policies of EU countries of skid resistance, rolling resistance and noise emissions

...current status (concerning skid resistance):

• skid resistance - considered as an important surface property• no formal EU policy has been issued yet• policies only on national level

Policies exist in many European countries …• with different focus• on different networks (... more and higher level policies for high-level

roads ...)• with different machines or underlying standards• with different “depth”

“Everybody is doing it, but everybody is doing it differently.”

WP1: Policies of EU countries of skid resistance, rolling resistance and noise emissions

...recommendation for future harmonised policies – skid resistance:

• apply to Level 1 and Level 2 networks (motorways and principal roads linking major towns)

• apply to in-service roads (not to new asphalt surfacings) - the network should be monitored every year; maximum: every 3 years, in both directions

• measurement technique - Continuous measurement using a device for which there is an established standard (e.g. a CEN TS)

• values averaged over not more than100 m for comparison with thresholds

• Threshold levels will be based on the risk of skidding on different types of site with the overall objective of equalising skidding accident risk across the network.

• …

Topics:

• Test methods and reference surfaces for skid resistance in EU member states

• Differences, advantages/disadvantages of harmonization approaches

• Suggest a harmonization method (reference device and surfaces)

• Road map/implementation plan (2010, 2015, 2020)

WP2: Harmonisation of skid-resistance test methods and choice of reference surfaces

WP2: Harmonisation of skid-resistance test methods and choice of reference surfaces

• 23 different devices for measuring skid resistance identified – devices mostly used: pendulum, SCRIM/SKM, GripTester

• measuring principles: Longitudinal (LFC) and sideways (SFC) friction coefficients

• slip ratios varying from ABS to locked wheel

• different test tyres

• different operating conditions

Some projects on skid resistance measurement harmonization were executed, but ... no common scale or harmonized method available yet

18/06/2009 Drafted by P G Roe, suggestions by MT Do

Spec. for new device

Conversionsdeveloped

Measurement standard written

QA/calibrationProcedures established

New machine developed

Existing single machine chosen as reference

Existing device type identified as reference

Ref. fleetidentified

HARMONISED EU SYSTEM

Reference group principles chosen

CC

BB

D1D1

D2D2

COMMON SCALE

OPTIONAL USE COMMON SCALE

AA

Determination of the common scale EU application

EE

national transition to common scale

FULL EU STANDARDISATION

national transition to standard scale Replace national fleets

with standard device

CC Common Scale harmonising by reference to average of a group of machines of a single device type.

BB Common Scale harmonising by reference to the average of a group of machines from different device types but of similar operating principle.

AA Common Scale harmonising by reference to the average of all device types in use that have a defined technical specification.

Common Scale using one specified machine as the reference device.DD

Line DescriptionOptional use of common Scale for comparisons where a linked national device is available.

EE

All national fleets evolved to reference

device

Road Map

Topics:

• describe different parameters of road surfaces and tyres

• identify interdependencies

• recommendations for optimisation of road surfaces and tyres

• identify lack of knowledge and proposals for further research concerning the optimisation of road surfaces and tyres

WP3: Road surface properties – skid resistance / rolling resistance / noise emissions

Problems – optimising surface properties

Problems:

•currently surfaces and tyres – optimised separately

various aims for optimising, but similar focus (e.g. road - high skid resistance; tyre – wet friction)

different parameters for optimising

surfaces tested with specified methods – surfaces are optimised according to the test methods

tyres tested on specified surfaces – especially according to ISO 10844

•surfaces and tyres – optimised mostly with regard to one of the three surface properties

can be influenced

can‘t be influenced

can be partly influenced

Surface parameters vs. road surface properties

Interdependency matrix – surface parameters (excerpt)

parameters (asphalt surfaces) SR RR NE

aggregate properties

• shape +/o ? +

• angularity + - o

• polishing resistance + ? o

mixture parameters

• max aggregate size + + +

• binder content +/- ? +/-

• void content +/- + -

laying & compacting

• chipping material – aggregate size + + +

• chipping material – polishing resistance

+ ? o

• degree of compaction ? ? -

finished surface

• layer thickness ? ? +

• absorption o o +

• shape factor ? ? +

... • ... ... ... ... ...

still knowledge gaps research

needs

Future research – research areas

•identified thirteen main research areas

most important - how to measuring and interpreting texture as well as the contact patch of a tyre on the surface with regard to the three surface properties

divided in surface parameters (including measuring systems and environmental parameters), tyre parameters (including measuring systems and environmental parameters) and surface/tyre interaction - simulation models

•cover a period of about 20 years

WP4: Environmental effects and impact of climatic change

Topics:• Environmental implications of optimising skid resistance

Establish the importance of the various factors involved Establish current state of knowledge

• Identify areas for future research on environmental effects• Consider potential impact of climate change

WP4: Environmental effects and impact of climatic change

Strand 1: The influence that providing harmonised/optimised skid resistance could have on the environment

Strand 2: The effect of climate change on skid resistance

• Increased use of polish resistant aggregates (effects of quarrying and production, emissions from transportation, increased tyre wear particle emissions, increased rolling resistance fuel consumption and GHG and other exhaust emissions, reduced maintenance?)

• Increased texture depth (increase in noise)

• Likely scenarios for temperature, rainfall patterns, etc

• How skidding risk may change• How to address these changes – material

specifications (texture depth, drainage, ...)• Impact on harmonised/optimised skid

resistance (Including measurement techniques/survey strategies, will surface characteristics change over time (In different ways? Or on different timescales?))

Following points were discussed:

Webpage – public part

http://tyrosafe.fehrl.org

(Documents – public)

• presentations of the Workshops• deliverables• other publications

Thank you for your attention

and interest

on behalf of the TYROSAFE team!