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A STUDY ON THE USE OF PLASTIC FIBER MATERIALS

AS AN ALTERNATIVE SOLUTION FOR

SOIL STABILIZATION

A Research Report

Submitted to

The Faculty of Engineering Department

University of Southeastern Philippines

Bislig Campus

In Partial Fulfillment of the Requirements

for the Degree of Bachelor of Science

in Civil Engineering

Submitted by

Cristhianares L. Obo

Andrialyn B. Ytom

March 2014

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APPROVAL SHEET

This undergraduate thesis entitled “A STUDY ON THE USE OF PLASTIC FIBER

MATERIALS AS AN ALTERNATIVE SOLUTION FOR SOIL STABILIZATION”

prepared and submitted by CRISTHIANARES L. OBO., and ANDRIALYN B. YTOM, in

partial fulfillment of the requirement for the degree, Bachelor of Science in Civil Engineering,

has been examined and recommended for acceptance, and approval.

ENGR. SHEILA B. CABERTE

Adviser

PANEL OF EXAMINERS

APPROVED by the Committee on Oral Examination with a grade of ________.

ANASTACIO PANTALEON, Ph.D.

Chairman

ENGR. WELKIE A. TIONKO ENGR. HENDON D LAMANILAO

Member Member ________________________________________________________________________

ACCEPTED as partial fulfillment of the requirements for the Degree of Bachelor of

Science in Civil Engineering.

AMOR D. DE CASTRO

Acting Dean

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ABSTRACT

A study of soil stabilization using fiber plastic material as an alternative solution is a

research which asses the physical properties of soil, such as increasing shear strength, bearing

capacity etc. that can be done by use of controlled compaction and compressive tests. This

study is conducted to investigate the possibility of utilizing waste plastic materials, cut-

fibered-striped, and mix with soil, as an effective soil stabilizer. This project involves the

detailed study on the possible use of waste plastics for soil stabilization. The analysis was

done by compaction and conducting unconfined compression tests on soil reinforced with

random plastic strips.

Compressive Strength and Shear Strength

The comparison of test results with 0% and 2% plastic strips was assessed when the

soil was soak in water in 24 hours. With the comparison of the said samples will determine if

the treatment soil will gain compressive strength and shear, gaining these two values are

enough to satisfy the study that the admixture is good stabilizer, if it decrease the said

admixture is not a good stabilizer. The Standard Compaction tests will be done to assess the

amount of compaction and the water content required in the field. The water content at which

the maximum dry density to attain is obtained from the relationships provided by the tests.

This be done by mixing soil with varying percentages (0.0%, and 0.2%) of plastic strips in soil

stabilized with various plastic sizes, soil stabilized with uniform sizes and soil stabilized with

optimum percentage of plastic strips.

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Dedication

This Research Paper is lovingly dedicated to our respected family who had been our constant

source of inspiration. They have given us the drive and discipline to tackle any task with

enthusiasm and determination. Without their love and support, this project would not have

been made possible.

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ACKNOWLEDGMENT

In accomplishing this kind of study, it is necessary to have a company, to seek

assistance in terms of financial, knowledge and other support that are done in different ways.

For everything that we had received, we would like to extend our appreciation especially to

the following:

To God, for he blessed us everything, especially the strength and the presence of mind

which we mostly needed through the time of our analysis or study, that also gives us the will

and to stay focus because we must consider the other subjects involved during the period of

this research taken.

To our adviser, Engr. Shiela Caberte, guiding and for teaching us essential proper

ways in conducting this study for giving us her consideration, patience, thought and

knowledge without hesitation, and for not giving up on us and did all she can to help us which

gives us more confidence to ourselves. Without her assistance we would not able to put this

topic together.

To Dr. Anastacio Pantaleon, our panel chairman along with Engr. Welkie Tionko and

Engr. Hendon Lamanilao as panel members. We are very grateful for they truthfully give us

their comments and advice which we had accepted and done for this study, particularly in

aspects that we had missed or we did not considered. We are very aware in their suggestion to

make this study an effective one.

To Engr. Adam Macapili, as our instructor for this research, who taught us the basic

and proper writing format of thesis, how it is handled up to its completion and the formal way

of defense.

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To the staff and personnel of DPWH, Bislig City Ecological Solid Waste

Management, QSTI who willingly offer us the reliable source and some financial support

which we needed primarily and the other documents that supports the rest of the papers.

To our family as our inspiration, for their unconditional support both financially and

moral. In particular, they give us their patience and understanding. Their faith gives us more

courage to preserve and work harder.

-The Researchers

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TABLE OF CONTENTS

PAGE

TITLE PAGE i

APPROVAL SHEET ii

ABSTRACT iii

DEDICATION iv

ACKNOWLEDGMENT v

TABLE OF CONTENTS vii

LIST OF FIGURES ix

LIST OF PHOTOS

Chapter

I. INTRODUCTION

Statement of the Problem 2

Objectives of the Study 3

Significance of the Study 4

Scope and Limitations of the Study 5

Definition of Terms 6

II. REVIEW OF RELATED LITERATURE

Related Literature 8

Related Studies 11

Concluding Remarks 18

III. METHODOLOGY

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Research Design 19

Series of works 19

Research Materials 20

Preparation of Samples 21

Test to be performed 22

Setting 22

IV. PRESENTATION, ANALYSIS AND

INTERPRETATION OF DATA

V. SUMMARY, CONCLUSIONS AND RECOMMENDATIONS

Summary 26

Conclusions 26

Recommendations 27

BIBLIOGRAPHY

APPENDIX

Location of QSTI 31

Grain Size Analysis, T-99, UCT results of 0% 32

T-99, UCT results of 2% 34

Photos 43

Curriculum Vitae 50

Biographical Sketch 53

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LIST OF FIGURES

PAGE

FIGURE 1. Conceptual Framework 5

FIGURE 2. Location Map of Qualitest Solutions and Technologies.Inc. 22

FIGURE 3: Laboratory Compaction graph for 0% and

2% plastic admixture in a soil 24 hour soak 23

FIGURE 4: Unconfined Compressive Chart of 0% and 2%

plastic admixture in a soil 24 hours soak water 24

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LIST OF PHOTOS

PAGE

PHOTO 1-11. Preparation of Testing Materials 44

PHOTO 12-16. Preparation of Soil Samples and admixtures 45

PHOTO 17-18. Weighing of Samples and Materials 46

PHOTO 25-38. Preparation and Performing Standard Compaction tests 47

PHOTO 39-44. Preparation and Performing UCT 48

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CHAPTER 1

INTRODUCTION

In any land-based structure, the foundation is very important and has to be strong to

support the entire structure. In order for the foundation to be strong, the soil around it plays a

very critical role. So, to work with soils, having the proper knowledge about their properties

and factors which affect their behavior is essential. The process of soil stabilization helps to

achieve the required properties in a soil needed for the construction work (Principles of

Geotechnical Engineering, Braja M. Das).

From the beginning of construction work, the necessity of enhancing soil properties

has come to the light. Ancient civilizations of the Chinese, Romans and Incas utilized various

methods to improve soil strength etc., some of these methods were so effective that their

buildings and roads still exist (Soil Stabilization, Arpan Sen).

For many years, engineers have used additives such as lime, cement and cement kiln

dust to improve the qualities of readily available local soils. Laboratory and field performance

tests have confirmed that the addition of such additives can increase the strength and stability

of such soils. However, the cost of introducing these additives has also increased in recent

years. This has opened the door widely for the development and introduction of other kinds of

soil additives (Soil Stabilization: Principles and Practice, Owen Graeme Ingles, J. B.

Metcalf).

Waste plastic materials are increasing in daily basis causing increased environmental

concerns. Driven by today’s technologies, waste plastic materials can be recycle but a small

percentage of it are recycled. Studies show that burying plastics is better than burning. The

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use of plastic waste if buried is a great challenge for civil engineering in utilization and

making it more useful for improving the soil characteristics and to solve problems related to

the disposal of waste plastic material (Raising Plastic Awareness, New York Times-August 15,

2011).

Meanwhile in the Philippines stabilization only using cement as soil stabilizer is

already approved by the Philippine Department of Public Works and Highways (DPWH) and

is already included in their Blue Book (Soil Stabilization in the Philippines, dpwh..gov.ph).

Here, in this project, soil stabilization will be done with the help of waste plastic fiber

or PPL fiber plastic materials. This might become a new technique of soil stabilization that

can be effectively use to meet the challenges of society, to reduce the quantities of waste,

producing useful material from non-useful waste materials that lead to the foundation of

sustainable society.

Statement of the Problem

Due to massive increasing of waste plastic materials in our country causing serious

environmental concerns, people are finding ways to minimize the pollution by recycling then

using waste plastic materials as an soil stabilizer is an initiative for civil engineers and

geotechnical engineers in preserving the nature by minimizing pollution caused by

uncontrolled human activities.

Air pollution, noise and vibrations, impacts on ecological balances or sometimes risk

of water contamination, electromagnetic induction are considered the main environmental

questions related to the construction and operation of transport systems. Scientific and

professional communities all over the world are involved in the study of these questions

engaging human and financial resources. In the last decade the know-how in this field has

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increased and the knowledge widely disseminated. However there are issues related to the

construction of infrastructures that are often neglected in terms of environmental assessment.

Sometimes they have implications to the environment that are much more relevant in addition

to traditional questions such as noise or air pollution. This is the case in the use of alternative

materials, stabilization of soil and recycling, which is the topic of this paper. The technique of

soil stabilization is usually adopted with the purpose of rendering plastic soils coherent to the

standards and requirements of engineering projects. The issue is always considered under a

construction perspective and environmental benefits are often neglected.

This study is conducted to investigate the possibility of utilizing waste plastic

materials, cut-fibered-striped, and mix with soil, as an effective soil stabilizer. And since

plastics are abundant and rarely used in soil related projects. Thus, the researchers attempted

to answer the following:

1. What are the Compressive Strength and Shear/Bearing Capacity of the 0% plastic fiber

admixture?

2. What are the Compressive Strength and Shear/Bearing Capacity of the 2% plastic fiber

admixture?

3. What is the difference of the result on Compressive Strength and Shear/Bearing

Capacity of the 0% and 2% plastic fiber admixtures?

Objectives of the Study

The objective of this study is to conclude that whether plastic materials can be a good

stabilizer or not, thus researchers aims:

1. To determine the Compressive Strength, Shear/ Bearing Capacity of the 0% plastic

admixture.

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2. To determine the Compressive Strength, Shear/Bearing Capacity of the 2% plastic

admixture.

3. To differentiate the results of the 0% and 2% plastic admixture with regards to

Compressive, and Shear/Bearing Capacity done by the Unconfined Compressive Test

on a 24 hours soak process.

Significance of the Study

Soil stabilization using waste plastic materials is an alternative method for the

improvement of sub-grade soil of pavement. It can significantly enhance the properties of the

soil used in the construction of road infrastructure. Results include a better and longer lasting

road with increased loading capacity and reduced soil permeability. This new technique of

soil stabilization can be effectively used to meet the challenges of society, to reduce the

quantities of waste, producing useful material from non-useful waste materials that lead to the

foundation of sustainable society. It can be effectively used in strengthening the soil for road

embankments and in preparing a sub base for the upper pavement structure. Since it could

increase the bearing capacity of soil considerably, the land use can be increased. It can lower

the road construction and maintenance costs while increasing the overall quality of its

structure and surface. The promise that soil stabilization technology can actually improve the

mechanical qualities of local road soil so that stronger, more durable roads can be built has

prompted national road ministries here and also around the world to conduct extensive testing

to verify that this new technology could be cost-effective. The positive result of this research

will might become a new era in soil stabilization technology that will be increasingly being

used in both constructing and improving/rehabilitating un-surfaced and paved roads

worldwide especially here in our local.

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Scope and Limitations of the Study

With the limited time and lack of financial capabilities of the researchers, the project

will have the following scope and limitations:

1. The research is only limited just to show the results conducted through test.

2. The research is to conduct a test of dark reddish gray clays with few sands.

3. The design of the soil relating to stabilization is not considered.

4. The soil is limited on a 24 hour soak UCS test process.

5. Financial capabilities of the researchers are very limited.

6. Only to identify that whether plastic can be a good soil stabilizer or not.

Conceptual Framework

Independent Dependent

`

Figure 1.0 Schematic diagram of the Study

Figure 1.0 shows the schematic diagram of the study in which consists of independent

and dependent variables. The Soil and plastic strips are manipulated in this experiment.

Moreover, the degree of efficacy and the concluding outcome of the examination will depend

Stabilization Mixture

1. Soil

2. Plastic strips

Performance of Stabilization

1. Compaction

2. Shear Capacity

3. Compressive Strength

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only to the components used by the researchers in getting the Bearing, Shear and Load

capacity of the soil.

Definition of terms

AASHTO. American Association of State Highway and Transportation

Officials.

ASTM. American Society for Testing Materials

Atterberg Limit. Limits of different ground consistencies conventionally

established: liquid state, plastic state, solid state with shrinkage, solid state without

shrinkage. Each state has limits which depend on the water content of the ground and

which are: liquid limit, plastic limit and shrinkage limit.

California Bearing Ratio. A number that expresses in percentage the ratio

between the pressures that generate a given penetration, on the one hand in the studied

material, and on the other hand in a reference material.

Compressive strength. is the capacity of a material or structure to withstand

loads tending to reduce size.

Consolidation. An operation for strengthening makes firm, etc., a soil or a

construction.

Limit of saturation. The water content from which water does not permeate in a

material would stream if the ground was inclined.

Liquid limit or limit of liquidity. The water level at which the ground behaves

like a liquid and flows under its own weight or the influence of external loads.

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Plastic limit or plasticity limit. The state of a ground that corresponds to

passing from a plastic state to a solid state.

Plastic. Macromolecular material which has a certain plasticity, that is to say

apt to get bent (out of shape) in a permanent way at a given temperature. 2. Of a

substance which gets out of shape under the effect of an external force and which

keeps the acquired shape without rupture.

Shear strength. is a term used in soil mechanics to describe the magnitude of

the shear stress that a soil can sustain. The shear resistance of soil is a result of friction

and interlocking of particles, and possibly cementation or bonding at particle contacts.

Shear Strength. The resistance to the deformation caused by the shear stress.

Shrinkage limit. The water content below which the material is dried without

decreasing its volume.

Soil. dark reddish gray clays with few sands.

Stabilization. The transformation and improvement of an undisturbed soil by

addition of a suitable binder or mechanically in order to make it suited to the required

purpose (strong roll surface, weather resistance, etc.). Syn. with CONSOLIDATION

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CHAPTER 2

REVIEW OF RELATED LITERATURE

This section presents the relevant literature and studies conducted which are essential

in the development of the whole study on using waste plastic material as an alternative

solution in soil stabilization.

Related Literature

2.1 Soil Stabilization

Soil stabilization is the process of altering some soil properties by different methods,

mechanical or chemical in order to produce an improved soil material which has all the

desired engineering properties. Soils are generally stabilized to increase their strength and

durability or to prevent erosion and dust formation in soils. The main aim is the creation of a

soil material or system that will hold under the design use conditions and for the designed life

of the engineering project. The properties of soil vary a great deal at different places or in

certain cases even at one place; the success of soil stabilization depends on soil testing.

Various methods are employed to stabilize soil and the method should be verified in the lab

with the soil material before applying it on the field.

Principles of Soil Stabilization:

• Evaluating the soil properties of the area under consideration.

• Deciding the property of soil which needs to be altered to get the design value and

choose the effective and economical method for stabilization.

• Designing the Stabilized soil mix sample and testing it in the lab for intended stability

and durability values.

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2.1.2 Needs & Advantages

Soil properties vary a great deal and construction of structures depends a lot on the bearing

capacity of the soil, hence, we need to stabilize the soil which makes it easier to predict the

load bearing capacity of the soil and even improve the load bearing capacity. The gradation of

the soil is also a very important property to keep in mind while working with soils. The soils

may be well-graded which is desirable as it has less number of voids or uniformly graded

which though sounds stable but has more voids. Thus, it is better to mix different types of

soils together to improve the soil strength properties. It is very expensive to replace the

inferior soil entirely soil and hence, soil stabilization is the thing to look for in these cases.

It improves the strength of the soil, thus, increasing the soil bearing capacity.

It is more economical both in terms of cost and energy to increase the bearing capacity

of the soil rather than going for deep foundation or raft foundation.

It is also used to provide more stability to the soil in slopes or other such places.

Sometimes soil stabilization is also used to prevent soil erosion or formation of dust,

which is very useful especially in dry and arid weather.

Stabilization is also done for soil water-proofing; this prevents water from entering

into the soil and hence helps the soil from losing its strength.

It helps in reducing the soil volume change due to change in temperature or moisture

content.

Stabilization improves the workability and the durability of the soil.

A plastic material is any of a wide range of synthetic or semi-synthetic organic solids

that are moldable. Plastics are typically organic polymers of high molecular mass, but they

often contain other substances. They are usually synthetic, most commonly derived from

petrochemicals, but many are partially natural. Most plastics contain other organic or

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inorganic compounds blended in. The amount of additives ranges from zero percentage for

polymers used to wrap foods to more than 50% for certain electronic applications. The

average content of additives is 20% by weight of the polymer. Fillers improve performance

and/or reduce production costs. Stabilizing additives include fire retardants to lower the

flammability of the material. Many plastics contain fillers, relatively inert and inexpensive

materials that make the product cheaper by weight. Typically fillers are mineral in origin, e.g.,

chalk. Some fillers are more chemically active and are called reinforcing agents.

Due to their relatively low cost, ease of manufacture, versatility, and imperviousness

to water, plastics are used in an enormous and expanding range of products, from paper clips

to spaceships. They have already displaced many traditional materials, such as wood, stone,

horn and bone, leather, paper, metal, glass, and ceramic, in most of their former uses.

Most plastics are durable and degrade very slowly; the very chemical bonds that make

them so durable tend to make them resistant to most natural processes of degradation.

However, microbial species and communities capable of degrading plastics are discovered

from time to time, and some show promise as being useful for bioremediating certain classes

of plastic waste.

The effect of plastics on global warming is mixed. Plastics are generally made from

petroleum. If the plastic is incinerated, it increases carbon emissions; if it is placed in a

landfill, it becomes a carbon sink although biodegradable plastics have caused methane

emissions. Due to the lightness of plastic versus glass or metal, plastic may reduce energy

consumption. For example, packaging beverages in PET plastic rather than glass or metal is

estimated to save 52% in transportation energy.

Production of plastics from crude oil requires 62 to 108 MJ of energy per kilogram

(taking into account the average efficiency of US utility stations of 35%). Producing silicon

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and semiconductors for modern electronic equipment is even more energy consuming: 230 to

235 MJ per 1 kilogram of silicon, and about 3,000 MJ per kilogram of semiconductors. This is

much higher, compared to many other materials, e.g. production of iron from iron ore requires

20-25 MJ of energy, glass (from sand, etc.) - 18-35 MJ, steel (from iron) - 20-50 MJ, paper

(from timber) - 25-50 MJ per kilogram.

Related Studies

The use of fibers for soil stabilization dates back to biblical times when straw was

mixed with clay (Freitag, 1986). Modern literature regarding the use of fiber stabilization

starts in Gray and Ohashi (1983) study of fiber reinforcement of beach sand. They concluded

that fibers improve shear strength characteristics of clean beach sand and recommended

further research that continues to the present. Literature published after 1983 includes testing

on compressive, tensile and shear strength of soil reinforced with fibers, as well as, resistance

to factors such as freezing and thawing and soaking and drying.

Chemical additives for soil stabilization include products produced by the commercial

sector which includes polymer emulsions, synthetic fluids and others. The use of chemical

additives for soil stabilization is a new area of research. Most of applications relate to military

rapid construction of roads and runways.

The combination of fiber and chemical soil stabilization was not introduced in the

literature until Hazirbaba et al. (2007) published findings on mixing silty sand with geofibers

and synthetic fluids. These results showed improvement in bearing capacity of the sand using

Earth Armor (Synthetic Fluid) and two inch tape geofibers.

Geofiber Stabilization of Sands. The benefits of adding geofibers to sands are provided

in the literature. One of the main benefits described is an increase in shear strength and

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ductility of sand. Several authors notedgains in shear strength and ductility in sand. Gray and

Ohashi (1983) indicated the fibers increase the peak shear strength and limit the post-peak

shear strength reduction. The shear characteristics of sands treated with geofibers were also

evaluated by Gray and Al-Refeai (1986) who were the first to look at randomly distributed

fibers in sand. The results indicated that increasing the fiber content increased peak shear

strength, as well as, making the sand more ductile. This behavior is similar to what is

observed by Gray and Ohashi (1983); the main differences come from fibers being oriented in

the early study and randomly distributed in the latter. In the oriented tests the reinforcement

area is increased which leads to the increase in shear strength. The first study that showed that

increasing fiber content above a certain point may have a detrimental effect on shear strength

was presented by Maher and Gray (1990). Triaxial testing was used to evaluate the effects of

fiber reinforcement on a total of nine sands. All sands tested showed shear strength increased

linearly with increasing amounts of fiber. For fiberglass fibers in dune sand at low confining

pressure shear strength approaches an asymptotic upper limit at 6% fiber content. Al-Refeai

(1991) showed an increase in shear strength of fine and medium sands using geofibers. This

focused mainly on fiber length and type and it was concluded that different fiber

characteristics can improve various aspects of the shear strength of soil.

The main objective of all of these studies was to evaluate sand and fiber characteristics

in order to predict the shear strength with fiber reinforcement. Variables such as soil

characteristics (particle size, shape, and gradation) and fiber properties (angle of orientation,

shape, finish, length, and modulus) were used to predict shear strength.

Another common theme in fiber reinforcement of sands is a change in the shape of the

failure envelope. Several authors describe a change in the failure envelope from the typical

linear failure envelope to either a bilinear or curved linear shape. A minimum confining

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pressure is described as the point where failure envelopes transition to become parallel with

untreated sand. The critical confining stress is governed by the modulus of the fibers used for

reinforcement.

Several authors including Gray and Ohashi (1983) describe a critical confining stress

where fibers slip or pull out below and rupture or yield above. Gray and Al-Refeai (1986)

found that the critical confining stress is greater if the surface roughness or interface friction

between the sand and fiber is greater. Maher and Gray (1990) discovered the behavior of the

failure envelope before the critical confining stress was found to behave in either a linear or

curved-linear manner depending on whether the soil was well-graded or uniform, respectively.

Al-Refeai (1991) confirmed the critical confining stress is depended on the modulus of the

fibers used for stabilization. Yetimoglu and Salbas (2003) and Ibraim and Fourmount (2006)

did not observed linear failure envelopes in direct shear tests on clean sand mixed with fibers.

Some authors conclude that geofibers increase the internal friction angle of sand while

others conclude there is either a decrease or no change. In oriented fiber arrays Gray and

Ohashi (1983) concluded that fibers have no effect on internal friction angle because above

the critical confining stress the failure envelopes were parallel. Direct shear tests performed on

sand mixed with fibers and cement by Craig et al. (1987) showed fibers positively affect

internal angle of friction. The fiber content and material affect the angle of internal friction

and cohesion of sand. When the soil-cement mixture was mixed with straight steel fibers the

friction angle decreased, with fiberglass fibers the opposite occurred. Al-Refeai (1991)

describes improvement using friction angle ratio to describe sands treated with geofibers.

Mesh fibers were found to improve the friction angle ratio better than fiberglass or pulp fibers.

Another example of fibers improving the friction angle of sand is presented by Consoli et al.

(1998). Triaxial testing of silty sand mixed with fibers caused the internal friction angle of

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sand to increase. Triaxial testing sand with polypropylene fiber reinforcement by Consoli et

al. (2007) showed an increase in internal friction of sand. Ibraim and Fourmount (2006)

conducted direct shear testing on sand treated with crimped polypropylene fibers which

increased internal friction angle.

Yetimoglu and Salbas (2003) used direct shearing tests on clean uniform sands treated

with fibers. The results of this testing showed increasing fiber content decreased the internal

friction angle of sand. These results are counter to what is found in other literature. The

decrease in internal friction angle could be attributed to the size of the shear box (2.4 inches x

2.4 inches by 1 inch deep) used in the study relative to the size of the fibers (0.8 inches long,

0.002 inches in diameter). It is possible that the fibers could not achieve a development length

necessary to provide added benefit. Another explanation for the decrease in internal friction

angle is a reduction in the fiber/soil interface. When fiber to fiber contact is greater than fiber

to soil contact the result could be a decrease in the internal angle of friction.

A small portion of available literature describes dosage rates and types of fibers to

meet a particular need. The first study where a particular sand was evaluated using a range of

fiber types was conducted by Ahlrich and Tidwell (1994). A combination of gyratory shear

and CBR testing was used to determine an optimum fiber content, fiber length, and fiber type

for beach sand. A 2 inch monofilament fiber at a 1% by dry weight dosage rate was found to

provide a 6% increase in CBR in the unsoaked condition. In the soaked condition all fiber

contents and configurations decreased the CBR value below the untreated sample. Dutta and

Sarda (2007) overlaid saturated sand with stone dust mixed with waste plastic strips. The

combination of stone dust with 4% waste plastic strips (1.4 inches long, 0.5 inches wide)

provided a 189% improvement in CBR value. Marandi et al. (2008) concluded 1.6 inch palm

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fibers at a dosage of 2.5% by dry weight provide the best Unconfined Compressive Strength

(UCS) for silty sand.

Geofiber Stabilization of Fine-Grained Soils.Literature shows that the addition of

geofibers to silts and clays can have positive effects. Low and high plasticity clays as well as

silts improve significantly with the addition of geofibers. The earliest study involving geofiber

stabilization of low plasticity clay comes from Freitag (1986). Three fiber types including

spun nylon string, polypropylene rope fiber, and fibermesh commonly used in concrete were

mixed with clay and tested using UCS. All fibers improved the UCS although the difference

between the strength results was negligible. The fiber type did not have an effect on the

strength of low plasticity clay. A study by Fletcher and Humphries (1991) on silt indicated

that monofilament and fibrillated fibers increase the bearing capacity of silt. The improvement

for silt treated with 0.75 inch long monofilament fibers at a content of 0.09% is 65%.

Fibrillated fibers of the same length and fiber content provide a 91% improvement. Jadhao

and Nagarnaik (2008) stabilized a sandy silt- fly ash mixture using 0.5 inch polypropylene

fibers at a1% fiber content.

Soil Stabilization Using Nontraditional Additives.Santoni et al. (2003) stabilized silty

sand with several nontraditional stabilizers, including acids, enzymes, lignosulfonates,

petroleum emulsions, polymers, and tree resins. UC tests were used as an index performance

test for all samples. Samples were prepared in moist and dry test conditions. A total of six

control samples, twelve nontraditional samples, and three traditional stabilizer samples were

tested. The results indicated three polymers have the potential to increase the strength of silty

sand in wet and dry conditions. For the traditional stabilizers, only cement provided

significant strength improvement. Both the traditional and nontraditional stabilizers lost

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strength under wet conditions. The optimum additive dosage for the polymer emulsion ranged

from 2.5% to 5% by weight of dry soil.

Tingle et al. (2003) looked at the stabilization of clay soils using several nontraditional

additives including several polymer emulsions. The purpose of this study was to develop a

compare effectiveness of several different liquid stabilizers. Low- and high-plasticity clays

were used in this study. Samples were subjected to wet and dry test conditions and were tested

using unconfined compression. The nontraditional stabilizers were compared to more

traditional ones, such as cement and lime. The unconfined compression results showed the

polymer emulsions to have variable improvements in the dry condition with minimal loss of

unconfined compressive strength in the wet conditions with both soil types. The optimum

amount of fluid for polymer emulsions was in the range of 2-5% by dry soil weight. Overall,

the products used in this study proved to be promising for use in low-volume roads.

Newman and Tingle (2004) investigated the use of four polymer emulsions on silty

sand specifically manufactured for their study. The level of 2.75% polymer emulsion by dry

mass of the soil was chosen as a basis of comparison for all of the polymer emulsions. This

was compared to Portland cement used at concentrations of 2.75%, 6%, and 9%. All samples

were subjected to unconfined compression testing. The toughness was used as an index

property to measure the effectiveness of the mix designs. The toughness is a measure of the

energy absorbed by the system per unit volume to the yield point. Three separate cure periods

were investigated: 24 hours, 7 days, and 28 days. Samples showed similar strength in the 24-

hour time period compared to the 7-day cure time, with the Portland cement samples seeing

the greatest increase in strength. Samples treated with polymer emulsions showed marked

improvement in Unconfined Compressive Strength (UCS) and toughness after a 28-day curing

27

period, with polymers showing significantly higher toughness values than the soil-cement

mixtures.

In the investigation done by S A Naeini and S M Sadjadi,(2008) ,the waste polymer

materials has been chosen as the reinforcement material and it was randomly included in to

the clayey soils with different plasticity indexes at five different percentages of fiber content

(0%, 1%,2%, 3%, 4%) by weight of raw soil. CBR tests are conducted by Behzad Kalantari,

Bujang B.K. Huat and Arun Prasad, (2010) and their experimental findings are analyzed with

the point of view of use of waste plastic fibers in soil reinforcement. Effects of Random Fiber

Inclusion on Consolidation, Hydraulic Conductivity, Swelling, Shrinkage Limit and

Desiccation Cracking of Clays (MahmoodR. Abdi, Ali Parsapajouh, and Mohammad A.

Arjomand, (2008)) point to the strength and settlement characteristics of the reinforced soil

and compared with unreinforced condition.

Megnath Neopaney, March 2012 concluded on his thesis Plastic for stabilizer that

compressive and bearing capacity can be significantly reduce if waste plastic strip is used as

soil stabilizing agent for sub-grade material. This suggests that the strips of appropriate size

cut from reclaimed plastic wastes may prove beneficial as soil reinforcement in highway sub-

base if mixed with locally available granular soils in appropriate quantity. The addition of

reclaimed plastic waste material to local soil increases the CBR. The maximum improvement

in CBR is obtained while using 0.5% plastics strips having aspect ratio 3. The CBR value at

AR 4 and 0.5% plastic strip decreased. The reinforcement benefit increases with an increase in

AR and percentage of strip content up to certain limit, and beyond that it reduces its strength.

The maximum CBR value of a reinforced system is approximately 1.70 times that of an

unreinforced system.

28

Moreover an environmental concern is also included by utilization of waste plastic

materials and they can be made useful for improving the soil characteristics and to solve

problems related to the disposal of waste plastic material.

Concluding Remarks

Use of plastic products such as polythene bags, bottles, containers and packing strips

etc. is increasing day by day. Disposal of the plastic wastes without causing any ecological

hazards has become a real challenge to the present society. Thus using waste plastic materials

as a soil stabilizer is an alternative, economical and gainful utilization since there is scarcity of

good quality soil for embankments and fills. Thus this project is to meet the challenges of

society to reduce the quantities of plastic waste, producing useful material from non-useful

waste materials that lead to the foundation of sustainable society.

29

CHAPTER 3

METHODOLOGY

This part discusses the methods and procedures used in this study. These include the

research design, series of work, research materials, setting, and the procedures of making the

materials being studied. The experimental program of this research will be carried out to

evaluate the effectiveness of plastic materials as soil stabilizer by following the existing

approaches conducted from local and other countries. Thus this is classified as quantitative

experimental research.

Research Design

The experimental research design will be employed throughout the scope of this study,

concerning to actual findings. This will be used to attain reliable data particularly on the basic

performance of the 2% plastic fiber as admixture in soil.

The two setups will be having the same type of soil. However, the first setup will have

0% plastic admixture or without any treatments while the second setup will be added 2%

plastic fiber.

3.1 Series of work are the following:

1. Specific gravity of soil

2. Determination of soil index properties (Atterberg Limits)

i) Liquid limit by Casagrande’s apparatus

ii) Plastic limit

3. Particle size distribution by sieve analysis

30

4. Determination of the maximum dry density (MDD) and the corresponding

optimum moisture content (OMC) of the soil by Proctor compaction test

5. Preparation of reinforced soil samples.

6. Determination of the shear strength by:

i) Direct shear test (DST)

ii) Unconfined compression test (UCS).

In order to conduct this study, various materials such as lateritic soil, plastic bottles

(both cut and uncut), sea sand and synthetic threads were to be use. The Standard Compaction

tests will be done to assessthe amount of compaction and the water content required in the

field. The water content at which the maximum dry density to attain is obtained from the

relationships provided by the tests. This be done by mixing soil with varying percentages

(0.0%, and 0.2%) of plastic strips in soil stabilized with various plastic sizes, soil stabilized

with uniform sizes and soil stabilized with optimum percentage of plastic strips. Load-

settlement graphs for each plate load test were to be drawn. For each load-settlement graph,

the load corresponding settlement will be noted. The ultimate load and corresponding

settlement of the plate can be determined from the load- settlement.

3.2 Research Materials

The soil sample Location was collected at Pag-asa District, Mangagoy, Bislig City, Surigao

del Sur. Admixture reinforcement is a short random plastic fibers and PPL fibers, 3cm x 1mm.

T-99 Compaction Materials, ASTM sieve apparatus, and Digital Weighing Machine are

prepared.

3.3 Preparation of samples

31

Following steps are carried out while mixing the fiber to the soil.

All of the soil samples will be compacted at their respective maximum dry density (MDD)

and optimum moisture content (OMC), corresponding to the standard proctor compaction

tests

1. Content of fiber in the soils is herein decided by the following equation: ρf=Wf/W

Where, ρf= ratio of fiber content

Wf = weight of the fiber

W = weight of the air-dried soil

2. The different value adopted in the present study for the percentage of fiber

reinforcement is 0, and 0.2.

3. In the preparation of samples, if fiber is not used then, the air-dried soil was mixed

with an amount of water that depends on the OMC of the soil.

4. If fiber reinforcement was used, the adopted content of fibers was first mixed into the

air-dried soil in small increments by hand, making sure that all the fibers were mixed

thoroughly, so that a fairly homogenous mixture is obtained, and then the required

water will be added.

5. Standard sieve analysis

6. Determine the Optimum Moisture Content (OMC) by measurement or by hand –feel.

7. Soil classification

8. Remove any organic matter

9. Grading: no stone larger than 20% of the layer depth being stabilized.

10. Use the desired testing ratio of the PPL fiber per m3 for test samples.

11. Add water or any liquid admixture at 1:4 ratios.

12. Compact in a standard cylindrical mold and extrude after compaction.

32

13. Conduct UCS Test

14. Computing of data and Results.

Test to be performed:

1. T-99 Compaction Test

2. Unconfined compressive strength test

Setting

On the scheduled date, the samples was transported to Qualitest Solutions &

Technologies, Inc. or QSTI, an engineering company that offers quality-testing services and

implement engineering solutions for the construction industry. So it can provide reliable

findings for soil stabilization. It is located at Carlos P. Garcia Highway (Diversion Road),

beside Ma. Bridge, Davao City.

Figure 2. Location Map of Qualitest Solutions and Technologies.Inc.

33

CHAPTER 4

PRESENTATION, ANALYSIS AND INTERPRETATION OF DATA

This chapter presents the data gathered in tabular form. Interpretation and analysis are

given to relate the significance in the workability and the compressive strength of the concrete

samples.

After the desired concrete mixture was obtained, the slump test was conducted. The

results were obtained through conducting standard compaction test in every percentage of

admixtures.

Figure 3: Laboratory Compaction graph for 0% and 2% plastic admixture in a soil 24 hours

soak in water

Figure 3 Shows the difference in moisture-density relation of the 0% and 2% plastic

additives on the soil sample which is soak in water for 24 hours. The 0% admixture attains a

maximum dry density of 1413.67 kg/cu.m, optimum moisture content of 24.91%, and a

1200

1250

1300

1350

1400

1450

0 5 10 15 20 25 30 35 40 45

Moisture Density Curve

Dry

Den

sity

(K

N/c

u.m

)

Moisture Content

0%

2%

34

74.08% degree of saturation while the 2% admixture attains 1361.4 kg/cu.m, 26.19%, and

72.07% respectively.

Furthermore, the figure illustrates that the plastic admixtures increases the moisture

content of the soil but decrease its density. It explains that in 24 hours soak in water test, soil

using of plastic as soil stabilizer is not effective which also relates with the results of Ahlrich

and Tidwell (1994) on their study about plastic fiber as soil stabilizer.

Figure 4: Unconfined Compressive Chart of 0% and 2% plastic admixture in a soil 24 hours

soak water.

Problem statement is determined that do fibred plastic materials increase or

decrease its compressive strength, and shear/bearing capacity. By the figure 4 shown above

explains that the use of 2% plastic as stabilizer is not effective. The 0% admixture arrives with

a 122.16 Kpa average compressive strength, and 78.71 Kpa undrained shear while the 2%

plastic admixture dramatically decreased its compressive strength and shear strength by 78.71

Kpa, and 39.32 Kpa respectively it means that the 2% plastic admixture as soil stabilizer

0

20

40

60

80

100

120

140

160

with 0%Sample 1

with 0%Sample 2

with 0%Sample 3

with 2%Sample 1

with 2%Sample 2

with 2%Sample 3

UCS (Kpa)

Undrained ShearStrength (Kpa)K

pa

123.1

107.4

135.99

61.65 53.97

68 54.05

27.03

67.85

33.93

114.23

57

35

decrease the compressive strength of the said soil by 35.54% and 35.71% in its shear strength.

The results was confirmed the statement cited by Megnath Neopaney (March 2012) on his

thesis Plastic for stabilizer that compressive and bearing capacity can be significantly reduce

if waste plastic strip is used as soil stabilizing agent for sub-grade material.

36

CHAPTER 5

SUMMARY, CONCLUSINS AND RECOMMENDATIONS

Summary

After differentiating results of the 0% and 2% plastic admixture with regards to

Compressive, and Shear/Bearing Capacity through Unconfined Compressive Test on a 24

hours soak process, the 0% admixture arrives with a 122.16 Kpa average compressive

strength, and 78.71 Kpa undrained shear strength while the 2% plastic admixture dramatically

decreased its compressive strength and shear strength by 78.71 Kpa, and 39.32 Kpa

respectively which corresponds with the studies of Megnath Neopaney, Ahlrich and Tidwell

on their thesis that compressive and bearing capacity can be significantly reduce if waste

plastic strip is used as soil stabilizing agent for sub-grade material.

Conclusions

From the findings of the study, therefore the researchers concluded that using of 2%

plastic fiber is not a good alternative for soil stabilizer through 24 hours soak UCS test. It

increases the optimum moisture content of the soil while it decreases the compressive and its

shear strength.

37

Recommendations

From the findings and conclusion of this study, the following recommendations are

presented:

1. To fully meet the reliable results it is recommended to conduct more tests and samples

related on this study such as test for unsoak soil, CBR, and etc.

2. For the future researchers, make sure that they will have enough budget to conduct this

kind of study.

3. It is recommended to have curing days of soil before testing the samples.

4. The study of using waste plastic as soil stabilizer can be a good alternative in

enhancing soil properties, since it is an uncommon topic; it is more interesting to

conduct more study about it.

38

BIBLIOGRAPHY

Arora, K. R. (2004). Soil Mechanics and Foundation Engineering. Standard

Publishers Distributors.

Arpan Sen and Rishabh Kashyap,(2012), “ Soil Stabilization using waste fiber

materials”.

Bateni, F. (2009). Stabilisation Mechanisms of oilpalm fruit bunch fibre

reinforced silty sand. Unpublished Ph.D. Thesis, University of Auckland. 5.

Purushothama Raj, P. (2005). Soil Mechanics

Chaosheng Tang, Bin Shi, Wei Gao, Fengjun Chen, Yi Cai, 2006. Strength and

mechanical behavior of short polypropylene fiber reinforced and cement stabilized

clayey soil. Geotextiles and Geomembranes 25 (2007) 194–202.

Consoli, N. C., Prietto, P. D. M. and Ulbrich, L. A. (1999). ‘‘The behavior of a

fibre-reinforced cemented soil.’’ Ground Improvement, London, 3(1), 21–30IS 2720 –

part (xiii) 1980-87

IS: 1888(1982), Method of Load Test on Soils. Indian Standards Institutions,

New Delhi.

Kumar, M. A., Prasad, D. S. V. and Prasadaraju, G. V. R. (2009). Utilisation of

industrial waste in flexible pavement construction. Electronic Journal ofGeotechnical

Engineering, Vol. 13

Mahmood R. Abdi, Ali Parsapajouh, and Mohammad A. Arjomand,(2008),”

39

Effects of Random Fiber Inclusion on Consolidation, Hydraulic Conductivity,

Swelling, Shrinkage Limit and Desiccation Cracking of Clays”, International Journal

of Civil Engineering, Vol. 6, No. 4, (284-292).

Meera Varghese and M. Veena,(2011), “Soil Stabilization using raw plastic

bottles”.

Methods of soil stabilization, December 24, 2010 [online] Available at: <

http://www.engineeringtraining.tpub.com/14070/css/14070_424.htm >

Purushothama Raj, P. (2005). Soil Mechanics and Foundation Engineering.

Pearson Education.

S. A. Naeini and S. M. Sadjadi ,(2008) ,” Effect of Waste Polymer Materials

on Shear Strength of Unsaturated Clays”, EJGE Journal, Vol 13, Bund k,(1-12).

The need for soil stabilization, April 9, 2011 by Ana [online] Available at: <

http://www.contracostalandscaping.com/the-need-for-soil-stabilization/>

Yetimoglu, T., Inanir, M., Inanir, O.E., 2005. A study on bearing capacity of randomly

distributed fiber-reinforced sand fills overlying soft clay. Geotextiles and

Geomembranes 23 (2), 174–183.

40

APPENDIX

41

Location Map of Qualitest Solutions and Technologies.Inc.

42

Grain Size Analysis, compaction result, and UCT result of 0% plastic admixture of soil

43

44

45

46

47

48

Compaction and UCT result of 2% plastic admixture of soil

49

50

51

52

53

PHOTOS

54

Photo 2 Photo 1-11. Preparation of Testing Materials

Photo 3 Photo 4

Photo 5 Photo 6

Photo 7 Photo 8

55

Photo 9 Photo 10

Photo 11 Photo 12 to 16. Preparation of Soil Samples and admixtures

Photo 13 Photo 14

Photo 15 Photo 16

56

Photo 17to 18. Weighing of Samples and Materials Photo 18

Photo 19 Photo 20

Photo 21 Photo 22

Photo 23 Photo 24

57

Photo 25to 38. Preparation and Performing Standard

Compaction tests. Photo 26

Photo 27 Photo 28

Photo 29 Photo 30

Photo 31 Photo 32

58

Photo 33 Photo 34

Photo 35 Photo 36

Photo 37

Photo 38

59

Photo 39 to 44. Preparation and Performing UCT Photo 40

Photo 41

Photo 42

Photo 43 Photo 44

60

CURRICULUM VITAE

61

CURRICULUM VITAE

OF

CRISTHIANARES L. OBO School I.D. No: 03-815

Panaghiusa District, Mangagoy, Cellphone No: +639307925140

Bislig City, Surigao del Sur, Philippines

I. PERSONAL INFORMATION

DATE OF BIRTH : November 07, 1989

PLACE OF BIRTH : Bislig City, Surigao del Sur

CIVIL STATUS : Single

RELIGION : Roman Catholic

HOME ADDRESS : Pag-asa, Mangagoy, Bislig City, Surigao del Sur

EMAIL ADDRESS : cristhianares_ariex.light@yahoo.com

II. EDUCATIONAL ATTAINMENT

COLLEGE : University of Southeastern Philippines – Bislig

Campus, Maharlika, Bislig City

DEGREE CONCENTRATION Bachelor of Science in Civil Engineering

HIGH SCHOOL : Saint Vincent de Paul College

Andress Soriano Ave., Bislig City, Surigao del Sur

March 2007

ELEMENTARY : Mangagoy North Elementary School

Mangagoy Highway, Bislig City, Surigao del Sur

March 2003

62

CURRICULUM VITAE

OF

ANDRIALYN B. YTOM School I.D. No: 10-066

Castillo Village, Mangagoy, Cellphone No: +639109932340

Bislig City, Surigao del Sur, Philippines

I. PERSONAL INFORMATION

DATE OF BIRTH : November 06, 1993

PLACE OF BIRTH : Bislig City, Surigao del Sur

CIVIL STATUS : Single

RELIGION : Roman Catholic

HOME ADDRESS : Castillo, Mangagoy, Bislig City, Surigao del Sur

EMAIL ADDRESS : andria_ytom2000@yahoo.com

II. EDUCATIONAL ATTAINMENT

COLLEGE : University of Southeastern Philippines – Bislig

Campus, Maharlika, Bislig City

DEGREE CONCENTRATION Bachelor of Science in Civil Engineering

HIGH SCHOOL : Bayugan National Comprehensive High School

Poblacion, Bayugan City

March 2010

ELEMENTARY : North Cabadbaran Elementary School

Cabadbaran City, Agusan del Norte

March 2006

63

BIOGRAPHICAL SKETCH

Cristhianares is an undergraduate student in Civil engineering with a good standing

status. He is a bonafide member of the Association of Civil Engineering Students (ACES) and

a Junior Philippines Institute of Civil Engineers (JPICE). Moreover, He passes some of

Philippine TESDA trainings in Plumbing, Computer Programming, and Computer Servicing.

He also attends seminars about environment, electronics, management, medical courses, and

technology. He was able to work in limited time and complicated situations. He also enjoys in

joining competitive computer gaming tournaments such as DOTA-2.

Andrialyn is an undergraduate student in Civil Engineering. He is a bona fide member

of the Association of Civil Engineering Students (ACES) and a Junior Philippines Institute of

Civil Engineers (JPICE).