Stripping Performance of Hot Mix

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UNIVERSITI TEKNOLOGI MARA

STRIPPING PERFORM ANCE OF HOT MIX

ASPHA LT (HMA) USING POLYM ER AND

HYDRATED LIME AS A DDITIVES

EKARIZAN SHAFFIE

Thesis submitted in fulfillment of the requ irem ents

for the degree of

Master of Science

Facu lty of Civil Eng ineering

Febru ary 2008


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ABSTRACT

Stripping is one of the common type of pavement failure found in asphaltic pavements.

Besides high traffic impact stress, climatic factor such as temperature and moisture also

have profound effect on the durability of hot mix asphalt (HMA) pavements. The

objective of this research is to evaluate and compare the stripping performance of

unmodified and rubber-polymer modified binder mixes with and without anti-stripping

additives in Superpave mix design (AASHTO TP4) procedure.

The study investigates four different dense graded Superpave HMA mixes. The first

mixture was a control specimen that contained no hydrated lime and unmodified binder.

The second mixture contained hydrated lime with unmodified binder. The third mixture

contained no hydrated lime but with rubber-polymer modified binder and the fourth

mixture contained hydrated lime with rubber-polymer modified binder. The hydrated

lime was used as anti-stripping additive. The addition of 40-mesh tyre crumbs and

polymer Ethylene-Vinyl-Acetate (EVA) into binder was used to prepare rubber-polymer

modified binder. The optimum percentage of rubber crumb and EVA polymer was

selected based on the previous research done by Ibrahim, (2005). The boiling water test,

the modified Lottman's test, and the indirect tensile resilient modulus test were used to

evaluate the stripping performance in these mixes. This study also documents the effect

of different temperature on tensile strength ratio (TSR) and resilient modulus ratio

(RMR) on the HMA mixtures. Comparison of the physical conditions such as strength or

resilient modulus of the conditioned and unconditioned samples were used as a measure

to evaluate the stripping potential in HMA pavement. Statistical analysis was then

carried out to evaluate the significance of rubber polymer and hydrated lime on the

stripping performance of HM A m ix.

Finding from this research work showed that rubber-polymer modified binder mixes

were found to exhibit better resistance to moisture damage compared to unmodified

binder mixe s. The results also show ed that the addition of hydrated lime as antistripping

additive is effective in all mixes, however greater resistance to moisture damage with

rubber-polymer modified binde r as compared to unmodified binder m ixes. In addition, it

could be noted that temperature significantly affects the performance of the hot mix

asphalt. Statistical analysis of TS R and RMR resu lts show there are significant different

for mix with the addition of hydrated lime and demonstrates a higher potential for

stripping resistance.

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Candidate's Declaration

I declare that the work in this thesis was carried out in accordance with the regulations

of Universiti Teknologi MARA. It is original and is the result of my own work, unless

otherwise indicated or acknowledged as referenced work. This thesis has not been

submitted to any other academic institution or non-academic institution for any other

degree of qualification.

In the event that my thesis be found to violate the conditions mentioned above, I

voluntarily waive the right of conferment of my degree and be subjected to the

disciplinary rules and regulations of Universiti Teknologi MARA.

Candidate 's Name : EKARIZAN BT. SHAFFIE

Candidate's Signature : U/Mfflt

t e : T/hl^

0

?


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A C K N O W L E D G E M E N T S

Firstlyandforemost, Iwould liketoexpressmygratitudetoAlmighty Allah S.W.T.for

givingme theguidanceandstrengthincompleting this master thesis with success.

I also wou ld liketoextentmygreatest thankyou to allthose who gavemethe po ssibility

to complete this thesis. Firstandforemost, I would liketo expressmy sincere gratitude

to my supervisor Associate Prof. Dr. Ir. Mohd Yusof Abd. Rahman for his advice,

comments, guidance, supportandencouragement during the com pletion of my study.

Special thanks are dedicated to Associate Prof. Dr. Ir. Zainab Mohamed as my

co-supervisor

for

sharing

her

ideas

and

information with me. This work would

not

have

been possible w ithout their utmost capability

and

intelligence.

Furthermore, I am also indebted to Prof. Mustaque Hussain (Kansas State University),

Associate Prof. Dr. Rosli Hainin, Prof. Mohamed Rehan Karim, Associate Prof. Dr.

Azemi Samsuri, Associate Prof. Dr. Ismail Atan, Pn. Juraidah Hj. Ahmad whose

assistance enable me to complete this project. Their guidance and support have

motivatedme tocomplete this project confidently.

I also wo uld like

to

thank

all

other parties, those wh o hav e involved d irectly

or

indirectly

in making this researchavery great success.

Finally, to my beloved family and friends, especially to my beloved husband Azman

Ibrahim whose patient and loves enabledme to complete this work. I owe you all the

heartiest gratitudeandthankyou foryour encouragement, inspirationandsuppo rt.

Thanksfor all thekindness.May the Almighty Allah S.W.T. blessus and bewithus all

the time.


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TABLE OF CONTENTS

TITLE PAGE

ABSTRACT

ACKNOWLEDGEMENTS

TABLE OF CONTENTS

LIST OF TABLES

LIST OF FIGURES

Page

1

ii

iii

iv

ix

xii

LIST OF ABBREVIATIONS

xiv

CHAPTER 1: INTRODUCTION

1.1 Background of Study 1

1.2 Problem Statement 5

1.3 Objectives g

1.4 Hypothes is g

1.5 Study Approach g

1.6 Scope of the Study g

1.7 Significance of the Study g

CHAPTER2: LITERATURE REVIEW

2.1 Mo isture Suscep tibility 10

2.2 Stripping

\ \

2.3 Moisture-Related Problems 12

2.4 Mo isture-Related Distresses 13

2.4.1 Bleeding, Cracking and Rutting 13

2.4.2 Ravelling 14

2.4.3 Localized Failure 15

2.5 Causes of Moisture-Related Distresses 15

2.5.1 Mo isture-Sensitive Aggregates 15

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2.13.5 Hyd ratedLime 37

2.14 Experience with Rubberised Bitumen Pavement in Malaysia 39

2 1 5 Modification of Bitumen using Ethelyne-Vinyl-Acetate(EVA ) 40

Plastomer

CHAPTER3 : RESEARCH METHODOLOGY

3.1 Experimental Process 42

3.2 Selection and Preparation of Materials 45

3.2.1 Rubb er-Polymer Modified Binder 45

3.2.2 Antistripping Additives Addition Procedure 47

3.2.3 Aggregate Gradation (ASTM CI 17 & ASTM C136) 47

3.2.4 Specific Gravity of Aggregate (ASTM C127 & 48

ASTM CI28)

3.2.5 Fine Aggregate Angularity (AASHTO TP 33) 49

3.2.6 Flat and Elongated Particles in Coarse Agg regate 50

(ASTMD4791)

3.2.7 Clay Content or Sand Equivalent (ASTM D2419) 59

3.2.8 Toughness (ASTM C131)

5 1

3.2.9 Soundness (ASTM C88)

5 2

3.2.10 Deleterious Material (ASTM C142)

5 2

3.3 Selection of Design Aggregate Structure 53

3.3.1 Establish Trial Blends 53

3.3.2 Com pact Trial Blends 54

3.3.3 Evaluate Trial Blends 55

3.3.4 Select Design Aggregate Structure 55

3.4 Selection of Design Asphalt Binder 57

3.4.1 Com pact Design Aggregate Structure at Varying 57

Asphalt B inder Content

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3.4.2 Determine Mixture Properties versus Asphalt Binder 58

Content

3.4.3 Select Design Asph alt Binder Content 58

3-5 Evalua tion of Mo isture Suscep tibility 59

3.5.1 Boiling Water Test (ASTM D 3625) 59

3.5.2 Modified Lottman Test (AASHTO T 283) 59

3.5.3 Resilient Modulus Test (ASTM D 4123) 64

CHAPTER

4:

RESUL TS, ANALYSIS AND DISCUSSION

4- ' Introduction 65

4.2 Selection of Materials 65

4.2.1 Aggregate Gradation 65

4.2.2 Specific Gravity of Agg regate 66

4.2.3 Consensus and Sources Aggregate Property Tests 67

4.3 Selection of Design Aggregate Structure 68

4.3.1 Establish Trial Blends 68

4.3.2 Compact Trial Blends 70

4.3.3 Trial Blends Evaluation 71

4.3.4 Select Design Aggregate Structure 72

4.4 Selection of Design Asph alt Binder 74

4.4.1 Design Aggregate Structure at Varying Asphalt

Binder Content

4.4.2 Determine Mixture Properties versus Asphalt

Binder Content

4.4.3 Select Design Asphalt Binder Con tent 77

4.5 Evaluation of Moisture Susceptibility 73

4.5.1 Boiling Water Test (ASTM D 3625)

7 8

4.5.2 Modified Lottman Test (AASH TO T 283) 79

4.5.3 Resilient Modulus Test (ASTM D 4123)

8 8

74

75

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4.6 Statistical Analysis 95

4.6.1 Statistical Analysis of Tensile Strength Data 95

4.6.2 Statistical Analysis of Resilient Mo dulus Data 93

4.6.3 Statistical Analysis of RMR and TSR Data j

0

Q

CHAPTER 5: CONCLUSION AND RECOMM ENDATION

5.1 The Suitability of Superpave System Using Local Aggregates \Q\

5.2 Effect of Unmodified and Rubber-Po lymer Modified Binder 101

on Stripping Performance ofHM mixes

5.3 Effect of Antistripping Additive on Stripping Performance of 102

HMA mixes

5.4 Overall Conclusion

5.5 Recommendations

103

103

REFERENCES

1 0 5

APPENDICES

Appendix A Tests Apparatus and Samplings

Appendix B

Superpave Mix Design Data and Analys is

Appendix C Data Sheets(Modified Lottman Test and Res ilient

Modulus Test)

Appendix D Data Sheets Statistical Analysis

Appendix E Publications

Vl l l


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LIST OF TABLES

N o.

Tit le Page

2.1 Factors Con tributing to M oisture-Related Distresses 13

2.2 G eneric Classification of Asphalt Add itives 32

3.1 Con sensus and Sources Aggregate Tests 45

3.2 Gradations 47

3.3 Superpave Aggregate Consensus Property Requirements 50

3.4 Gradation Criteria for 19mm Nom inal M aximu m Size Mixtu re 53

3.5 Gyratory Com pactive Efforts in Superpave Volum etric Mix 54

Design

3.6 Superpave Volum etric M ix Design Criteria 55

4.1 W ashed Sieve Ana lysis for Material Passing the0.075mm Sieve 65

4.2 Dry Sieve Gradation Analysis Result 65

4.3 Sum marized of Bulk and Apparent Specific Gravity of Agg regate 66

4.4 Sum marized of Agg regate Testing 66

4.5 Com bined Gradation for Each Blend 67

4.6 Com bined Ave rage Aggreg ate Bulk Specific Grav ity (G

S

b) and 68

Apparent Specific Gravity (G

sa

)

4.7 Th e Init ial Bind er Co nten t (Pb.initiai) 69

4.8 Theoretical ma ximu m specific gravity (Gmm) of Loos e M ixture 70

and Bulk specified g ravity of compacted m ixture (G

m

b)

4.9 Com paction Summ ary of Trial Blends 71

4.10 Estimated Volum etric and Density Properties 72

4.11 Averag e Theo retical M aximu m Specific Gravity (G

mm

) of Loose 73

Mixture and Average Bulk Specified Gravity of Compacted

Mixture (G

m

b)

4.12 Volumetric Properties and M ixture's Com paction 74

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4.13 Design M ixture Properties at Optimum Binder Content 76

4.14 Bo iling W ater Test Results 78

4.15 Indirect Tensile Strength (IDT) Resu lts for Unc onditioned and 79

Conditioned Samples for Binder Used at Different Test

Temperatures

4.16 Tensile Strength Ratio (%TSR) for Unm odified Binder and 81

Rubber-Polymer Modified Binder Mix at Different Test

Temperatures

4.17 Indirect Tensile Strength (IDT) Resu lts of Unco nditioned samples 82

for With and Without Hydrated Lime at Different Test

Temperatures

4.18 Indirect Tensile Strength Results of Cond itioned Sam ples for W ith 84

and Without Hydrated Lime at Different Test Temperatures

4.19 Tensile Strength Ratio (%TSR) Results for W ith and W ithout 85

Hydrated Lime at Different Test Temperatures

4.20 Indirect Tensile Resilient Mo dulus (ITRM ) Resu lts for 87

Unconditioned and Conditioned Samples for Binder Used at

Different Test Temperatures

4.21 Resilient mo dulus Ratio (%RM R) for Unm odified Bind er and 88

Rubber-Polymer Modified Binder Mix at Different Test

Temperatures

4.22 Indirect Tensile Resilient Mo dulus Resu lts of Unco nditioned 89

Samples for With and Without Hydrated Lime at Different Test

Temperatures

4.23 Indirect Tensile Resilient Mo dulus Resu lts of Cond itioned 91

Samples for With and Without Hydrated Lime at Different Test

Temperatures

4.24 Resilient M odulus Ratio (%RM R) Resu lts for W ith and W ithout 93

Hydrated Lime at Different Test Temperature

x


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4.25 Summ ary of Analysis of Variance (ANO VA), Mean and 95

Significance Value

4.26 Summ ary of Analysis of Variance (ANO VA ), Hom ogeneous 96

Subsets

4.27 Summ ary of Analysis of Variance (ANO VA ), Mean and 97

Significance Value

4.28 Paired Sam ples Test 98


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LIST OF FIGURES

No.

1.1

1.2

2.1

2.2

2.3

2.4

2.5

Titles

Maintenance Budget per Kilometer for Federal and State Roads

Study Approach

Typical Appearance of Stripping in Com pacted Mix

Sources of Water (Moisture) in an Asphalt Pavement Structure

Rutting in the Wheel Paths

Raveling of the Asphalt Pavement

Typical Localized Failure of HMA Pavement Due to Moisture

Page

3

7

11

12

14

14

15

2.6 Coating Without Chemical Bond in a Moist and Dry Environment 17

2.7 Stripping of Asph alt Film from the Agg regate Surface 18

2.8 Stiffness characteristics of Conv entional Binder and Ideal Modified 29

Binder

2.9 Effect of anti-strip agent on surface bon ding of aggregate and asphalt 36

3.1 Exp erimental Des ign of the Study 42

3.2 Procedu re for Selection Design Agg regate Structure 52

3.3 Proced ure for Selection of Design Asph alt Binder Con tent. 56

3.4 Outline Standard Procedure for Evaluation of Mo isture Susceptibility 59

4.1 The Gradation Chart for Each Blend 68

4.2 Graph of Volum etric Properties Vs Asph alt Content (%AC ) for Each 75

Mixture

4.3 Densification Curves at Nd

es

Verification 77

4.4 Indirect Tens ile Strength of Unco nditioned and Con ditioned 79

Samp les for Binder Used at Different Test Tem peratures

4.5 Com parison of Tensile Strength Ratio (TSR) for Binder Use d at 81


x


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4.6 Com parison of Indirect Tensile Strength of Unco nditioned Samples 83

for With and Without Hydrated Lim e at Different Test T emp eratures

4.7 Com parison of Indirect Tensile Strength of Con ditioned Samp les for 84

With and Without Hydrated Lime at Different Test Temperatures

4.8 Com parison of Tens ile Strength Ratio (TSR) for W ith and W ithout 86

Hydrated Lime at Different Test Temperatures

4.9 Indirect Tensile Resilient Mo dulus of Unco nditioned and 87

Conditioned Samples for Binder Used at Different Test Temperatures

4.10 Com parison of Resilient Mo dulus Ratio (RM R) for Binder Used at 88


4.11 Com parison of Indirect Tensile Resilient Mo dulus Results of 90

Unconditioned Samples for With and Without Hydrated Lime at


4.12 Com parison of Indirect Tensile Resilient Mo dulus Results of 91

Conditioned Samples for With and Without Anti-Stripping Additives

at Different Test Tem peratures

4.13 Com parison of Resilient Mo dulus Ratio (%RM R) for W ith and 93

Without Hydrated Lime at Different Test Temperatures

x


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LIST OF ABBREVIATION

A A S H T O

A S T M

A C W

DOT

ESALs

H M A

% G

m m

% G

m b

JKR

M H A

Njnitial

JN design

-N m aximum

NMAS

NCHRP

OAC

PEN

PG

PWD

SGC

SUPERPAVE

SHRP

VFA

VMA

Am erican Association of State High way and Transp ortation Officials

American Society for Testing and Materials

Asphalt Wearing Course

Department of Transport

Equivalent Single Axle Loads

Hot Mix A sphalt

Theoretical Maximum Density

Bulk specific gravity of aggregates

Jabatan Kerja Raya

Malaysian Highw ay A uthorities

Initial Compaction

Design Compaction

Maximum Compaction

Nominal Maximum Aggregate Size

National Cooperative Highway Research Project

Optimum Asphalt Content

Penetration

Performance Grade

Public Works D epartment

Superpave Gyratory Compactor

Superior Performing Asphalt Pavement

Strategic H ighway R esearch Program

Voids in Filled with Asphalt

Voids in Mineral Aggregate

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C H A P T E R 1

I N T R O D U C T I O N

1.1 Backg round of Study

Malaysia has been experien cing tremend ous develop men t in the national infrastructure

road network over the last decade. This has contributed to the accelerated growth in the

Malaysian economy. The Public Works Department alone is responsible to the total

extend of Malaysia roads network for about 61,075.32 kilometers of paved roads and

18,428.84 kilometers of unpaved roads and the Malaysia government spends on average

RM950 million in year 2005 for construction, maintenance and rehabilitation (JKR,

2005).

Malaysian economic growth in rural areas has been triggered by good and safe

roads and highways network system. Highway pavement design in Malaysia has been

adopting the Marshall Method of mix design. Unfortunately, this design method does

not account for local environment and materials characteristic that contributed to

pavement failure on Malaysian roads. Furthermore, studies had shown that climate,

traffic condition, type and use of the mix, characteristics of the asphalt binder and the

aggregate are factors that can accelerate premature pavement failures (Terrell et al.,

1994).

One of the most common problems in flexible pavement in Malaysia is aggregate

stripping. Stripping of the pavement has been defined as weakening or eventual loss of

the adhesive bond usually in the presence of mo isture between the aggregate surface and

the asphalt cement in a Hot Mix Asphalt (HMA) pavement or mixture (Roberts et al.,

1991).

When a weakening in the bond occurs, loss of strength of the HMA can be

sudden. Typically, stripping starts at the bottom of the HMA layer then propagate

upward. Stripping is one of the most difficult distresses to identify in hot mix asphalt


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asphalt mixture design and analysis system that was developed by the Strategic Highway

Research Programme (SHRP) in the United States in the early nineties was intended to

provide better performing asphalt pavements.

Figure 1.1: Maintenance budget per kilometer for federal and state roads

(San and Sufian, 2002)

Most states in the United States have already replaced traditional Marshall mixture

design with the Superpave mixture design (Asphalt Institute, 2001). Early success with

this system has shown the potential to reduce asphalt pavement rehabilitation and

maintenance cost significantly. The Superpave system represents an improved system

for specifying asphalt binders, mineral aggregates, asphalt mixture design, analyzing and

establishing pavement performance. Superpave mixes are designed to resist permanent

deformation, provide fatigue resistance, durability and resistance to moisture damage

(Asphalt Institute, 2001). This new mix design system could be the right solution to

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1.2 Problem Statem ent

Stripping of aggregate from asphalt binder has been a common problem that results in

premature pavement failures in Malaysia. Malaysia being in tropical climate receives a

significant amount of rainfall throughout the year. Besides climatic factor such as

temperature and moisture, high traffic impact stress also have profound effect on the

durability of Hot Mix A sphalt (HM A) pavem ents against stripping failures.

Stripping happens when water infiltrates between an asphalt film and the aggregate

surface, and replaces the asphalt ag gregate's coating. This situation causes a loss of bond

between the aggregate and the asphalt cement (Hunter et al., 2002). The most serious

consequence of stripping is the loss of strength and integrity of the pavement. Stripping

failures within the asphalt pavement structure can translate into various types of

pavement failure such as fatigue cracking, rutting, raveling and potholes. This condition

makes driving dangerous, and driving comfort and safety are often compromised. The

damage of asphalt pavements due to moisture also can significantly increase the

maintenance costs of a pavem ent and ultimately, reduce the life of the pavem ent.

Due to these problems, it has been seen increased interest to improve HMA mixture

properties for better performance and safe riding comfort. Therefore, there is a need to

introduce a new system of Superpave mix design to replace the current HMA mix for

improvement of pavement service life and eventually reducing the maintenance cost. It

is also crucial to evaluate stripping performance on modified binder with rubber-

polymer and also the addition of hydrated lime as antistripping additive to an HMA mix.

The need for evaluating the effectiveness of rubber-polymer modified binder and

antistripping additives to the HMA mixes is an important consideration in order to

reduce stripping problems and to create high pavements performance, and also to find

mixtures that can resist stripping problems due to moisture dam age.

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1.3 Objectives

The primary objective of this research is to evaluate HMA stripping performance under

different mix design. In achieving the main objective, the secondary objectives of the

research are;

i. To conduct HM A mixture design according to the Superpave system using

local aggregates w ithout and with additives,

ii. To evaluate stripping performance of unmod ified and rubber-polymer

modified binder of HMA mixes,

iii.

To evaluate the effects of antistripping additive on unmodified and rubber-

polymer modified binder of HMA mixes.

1.4 Hypothesis

Several hypo theses w ere formulated for this study as follows;

i. The addition of rubber-polymer into bitumen will improve the stripping

performance of HMA pavement,

ii. Higher tempe rature testing may reduce the strength of the asphalt mix.

1.5 Study App roach

The study approach mainly involves experimental work. The flow chart for the

research is shown in the Figure 1.2. The study focuses on the performance of Hot Mix

Asphalt (HMA) using Superpave methods. The Superpave mix design procedure

involves careful material selection and volumetric proportioning as a first approach in

producing a mix that will perform successfully. The four basic steps of Superpave

asphalt mix design are selection of material, selection of design aggregate structure,

selection of design asphalt binder content and evaluation of moisture susceptibility

using performance tests.

In this study, traffic level was selected based on common traffic level operating on most

Malaysia high way s. The traffic will be limited to medium to high roadway application.

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Studv objectives

Literature review

Material selection

v

Aggregate testing

1

Asphalt selection

v

Selection of Design Aggregate Structure

Selection of design asphalt binder content

i '

I Evaluation of moisture susceptibility using performan ce

Analysis and results

i

Conclusion

^

Conduct Superpave

Mix Designs

(S i Ndes ign=100

Final submission report and presentation

Figure 1.2: Study approach

In Superpave system, medium to high traffic loadings is equivalent to between 3 to 30

million design equivalent single axle loads (ESALs) with 20 years design life. The

Superpave mix design procedure is used to determine the design aggregate structure and

asphalt binder content. Superpave volumetric mix design properties (VMA, VFA,

percent air voids, and dust proportion) were analyzed based on the Superpave criteria.

These volumetric properties are very important to asphalt mixtures, because these

volumetric properties significantly affect the durability and stability of mixtures

(Asphalt Institute, 1996). The most important goal of the Superpave mix design is the

evaluation of the moisture susceptibility of the design asphalt mixture. The purpose of

7


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this study to evaluate HMA stripping performance of modified binder and also evaluate

the effects of antistripping additive on asphalt mixtures using performance tests in

Superpave mix design procedure. Data collected throughou t this study were analyzed

and summarized before proceeding to report writing.

1.6 Scop e of the Study

This study consisted of evaluating dense graded Superpave mixes consisting of granite

aggregate with a 19 mm nominal maximum size and two types of asphalt binder:

unmodified binder and rubber-polymer modified binder. Granite aggregates from

Hanson quarry, Semenyih was used in all asphaltic mixtures in this study. The asphalt

binder was provided by SHELL. Hydrated lime was used as an antistripping agent. A

total of 4 type hot mix asphalt (HMA) design mixtures were evaluated in this study; (a)

Unmodified binder without hydrated lime (UMB) mix as control mixture; (b)

Unmodified binder with hydrated lime (UMBL) mix; (c) Rubber-polymer without

hydrated lime (RPMB) mix; and (d) Rubber-polymer with hydrated lime (RPMBL) mix.

Tests to evaluate stripping performance are Boiling Water Test, Modified Lottman Test

and Resilient Modulus Test.

1.7 Significance of the Study

The efficiency of the design of hot mix asphalt (HMA) for road or highways

infrastructure plays an important role in a develop country with tropical climate for

better performance and safe riding comfort. Thus, it is important to look seriously at

alternative asphalt technologies to ensure that the pavement failure due to stripping of

our road can be eliminated. Malaysia is one of the countries that adopt the Marshall

method, the most common method widely used in HMA mix design until today.

However, the Marshall mix design method only use the basic performance tests such as

Marshall stability and flow. These tests are empirical and furthermore, the procedure

does not present a performance based test. The Superpave mix design is a new method

of mix design currently used in the United States to replace Marshall mix method. This

study conduct a Superpave mix design and analysis to provide better performing asphalt

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pavements. This new mix design system could be the right solution to replace the current

Malaysia HM A mix for improving the pavement service life and even tually reducing the

maintenance cost in the long run.

A solution for high performance HMA pavements are a crucial part of our nation's

strategy for building a high performance transportation network for the future. This

study concentrates on the effectiveness of antistripping additives and rubber-polymer

modified binder to the new HMA Superpave mix design. These new approach could be

the right way to create pavement systems that will perform to the highest expectations

for many years. With prolonged service life of pavement, substantial amount of money

can be saved from reduced maintenance work, reduced congestion, lower pollution and

user costs during road work and from the conservation of natural resources, such as road

building materials. The success of this research will contribute to determine the

suitability of the new system with additives to address Malaysian condition and also to

reduce stripping problems on Malaysian roads.

9

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