COMPARISON BETWEEN SUPERPAVE GYRATORY AND MARSHALL LABORATORY COMPACTION METHODS NAEEM AZIZ MEMON A project report submitted in partial fulfillment of the requirements for the award of the degree Master of Engineering (Transportation and Highways) Faculty of Civil Engineering Universiti Teknologi Malaysia 20 OCTOBER -2006
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COMPARISON BETWEEN SUPERPAVE GYRATORY AND MARSHALL LABORATORY COMPACTION METHODS
NAEEM AZIZ MEMON
A project report submitted in partial fulfillment of the
requirements for the award of the degree
Master of Engineering (Transportation and Highways)
Faculty of Civil Engineering
Universiti Teknologi Malaysia
20 OCTOBER -2006
To my beloved mother, father, wife and kids
ACKNOWLEDGEMENTS
It is with great joy and lightness of spirit that I offer my deepest, most
heartfelt thanks to ALLAH for lighting up my heart with the torch of Knowledge;
then to my father and my husband who have assisted and supported me in countless
ways as I journeyed through the process of undertaking, creating, and, at long last,
finally completing this project.
First, I would like to take this opportunity to thank my supervisor, Dr. Mohd
Rosli Bin Hainin, for his exceptional guidance and encouragement through out my
study and this research project. I would like to extend my cordial thanks to all the
staff persons of Faculty of Civil Engineering, UTM for helping me in many during
my research.
Special thanks are reserved to all my family members and friends for their
invaluable presence in hard times when I needed them.
I am most thankful to my mother, wife and uncle to be my spiritual
inspiration. They gave me a chance to figure out myself. I will always owe them for
giving me the time to do my masters when they needed me with them the most.
ABSTRACT
The last decade has witnessed a dramatic increase in vehicular traffic on
roads in developing countries like Malaysia. This has raised additional traffic,
augmented axle loads and increased tire pressure on pavements designed for earlier
era. In this regard, besides considering increasing the pavement thickness due to the
traffic loads , steps must also be taken to extend the pavement life by using different
compaction methods such as gyratory laboratory compaction method to have
durable mix and better simulate field conditions. However, the main shortcoming of
gyratory compaction method is that the gyratory compactor is very costly as seven
times more than that of the available Marshall hammer.To overcome that
shortcoming, studies have been done to compare both laboratory compaction
methods but more are needed to verify different findings according to different
conditions and climate. In this research four asphalt concrete mixes asphalt wearing
course(ACW)10, ACW14, ACW20 and ACB28 were designed using Marshall mix
design to evaluate HMA properties such as density and air voids. Based on the
Marshall results, specimens were fabricated to obtain the required number of
gyrations that could produce same results in terms of density. Using the equivalent
number of gyrations samples were designed using superpave to obtain the optimum
bitumen content (OBC). The results indicate that at 75 blows Marshall, the
equivalent number of gyrations for ACW10, ACW14, ACW20 and ACB28 are 105,
67, 58 and 107 respectively. The results also suggest that there is no significant
difference in OBC except for ACW10, which is 0.6%. This shows that numbers of
gyrations obtained are reasonable in comparing with 75 blows Marshall.
ABSTRAK
Dekad yang terakhir telah menyaksikan peningkatan yang mendadak dalam
lalulintas di jalan-jalan di negara-negara membangun seperti Malaysia. Ini telah
menambahkan pembebanan lalulintas, peningkatan beban gandar, dan pertambahan
tekanan tayar ke atas jalan yang direkabentuk untuk zaman terdahulu. Selain
daripada pertimbangan untuk meningkatkan ketebalan jalan akibat daripada beban
lalulintas, langkah-langkah juga haruslah diambil untuk memanjangkan jangka hayat
jalan dengan menggunakan kaedah pemadatan yang berbeza seperti kaedah
pemadatan putaran makmal untuk menghasilkan campuran yang lebih tahan lasak
dan menyerupai keadaan tapak. Walau bagaimanapun, masalah utama kaedah
pemadatan putaran ialah pemadat putaran ini lebih mahal harganya, tujuh kali
ganda daripada tukul Marshall yang sedia ada. Untuk mengatasi masalah ini, kajian
telah dijalankan untuk membandingkan kedua-dua kaedah pemadatan makmal
tersebut tetapi lebih banyak kajian diperlukan untuk mengesahkan keputusan yang
berlainan mengikut keadaan dan iklim yang berbeza. Dalam kajian ini, empat
campuran konkrit berasfal, lapisan haus konkrit berasfal (ACW)10, ACW14,
ACW20, dan ACW28, telah direkabentuk menggunakan rekabentuk campuran
Marshall untuk menilai sifat-sifat seperti ketumpatan dan lompang udara.
Berdasarkan keputusan Marshall, spesimen-spesimen dihasilkan untuk mendapatkan
bilangan putaran(gyration) yang diperlukan untuk memperoleh keputusan
ketumpatan yang sama. Dengan menggunakan bilangan putaran(gyration) yang
sama, sampel telah direkabentuk menggunakan Superpave untuk mendapatkan
kandungan bitumen yang optimum (OBC). Keputusan menunjukkan bahawa pada
75 hentakan Marshall, bilangan putaran(gyration) yang bersamaan untuk ACW10,
ACW14, ACW20, dan ACB28 adalah 105, 67, 58, dan 107 masing-masing.
Keputusan juga mencadangkan bahawa tiada perbezaan yang nyata dari segi OBC
kecuali ACW10, iaitu 0.6%. Ini menunjukkan bahawa bilangan putaran(gyration)
yang diperoleh adalah munasabah jika dibandingkan dengan 75 hentakan Marshall.
TABLE OF CONTENTS
CHAPTER TITLE PAGE
TOPIC i
DECLARATION THESIS ii
DEDICATION iii
ACKNOWLEDGMENT iv
ABSTRACT v
ABSTRAK vi
TABLE OF CONTENTS vii
LIST OF TABLES x
LIST OF FIGURES xi
LIST OF APPENDICES xii
1 INTRODUCTION 1
1.1 Introduction 1
1.2 Laboratory compaction 2
1.2.1 Compaction by Impact 2
1.2.2 Kneading compaction 3
1.2.3 Gyratory compaction 4
1.3 Problem statement 6
1.4 Objectives 6
1.5 Scope of study 6
1.6 Purpose of study 7
2 LITERATURE REVIEW 8
2.1 Introduction 8
2.2 Laboratory compaction 9
2.3 Factors affecting compaction 10
2.4 Asphalt Mix design 13
2.4.1 Mix design methods 13
2.4.2 Marshall Mix Design v/s Gyratory 13
Mix design
2.4.3 Gyratory v/s Marshall compactor 16
2.5 Pavement performance 19
2.6 Conclusion of the literature review 20
3 METHODOLOGY 23
3.1 Introduction 23
3.2 Operational framework 24
3.3 Preparation of material for mixes 27
3.3.1 Aggregates 27
3.3.2 Bituminous binder 28
3.3.3 Mineral filler 28
3.4 Sieve analysis 28
3.4.1 Dry sieve analysis 28
3.4.2 Washed sieve analysis 30
3.5 Aggregate blending 31
3.6 Determination of specific gravity for aggregate 32
3.6.1 Course aggregate 32
3.6.2 Fine aggregate 33
3.7 Laboratory Mix design 35
3.7.1 Marshall Mix design 35
3.7.1.1 Mix design preparations 35
3.7.2 Superpave mix design 39
3.7.2.1 Procedure 40
3.8 Measurement of density 43
3.8.1 Bulk specific gravity 43
3.8.2 Maximum Theoretical density 45
3.9 Data analysis 46
3.10 Summary 47
4 RESULTS AND DATA ANALYSIS 48
4.1 Introduction 48
4.2 Marshall test results 49
4.2.1 Optimum bitumen content 49
4.2.2 Density 49
4.3 Superpave test results 50
4.3.1 Gyrations 50
4.3.2 Optimum bitumen content 51
4.4 Discussions 52
5 CONCLUSIONS & RECOMMENDATIONS 54
5.1 Introduction 54
5.2 Conclusion 55
5.3 Recommendations 55
BIBLIOGRAPHY 57
LIST OF TABLES
TABLE NO. TITLE PAGE
2.1 Summary of engineering property comparison 15
3.1 Gradation limits for asphaltic concrete (JKR, 2005) 31
3.2 Asphltic concrete ranges (JKR, 2005) 32
3.3 Superpave gyratory compactive effort based on ESALs 41
3.4 Design Bitumen Contents (JKR/SPJ/rev2005) 43
3.5 Minimum sample size requirement for maximum theoretical 46
specific gravity (ASTM D 2041)
3.6 Sample table for data recording and calculation 47
4.1 Marshall test results 50
4.2 Equivalent number of gyrations to simulate density 51
4.3 Comparison of OBC 51
4.4 Comparison between Marshall and Gyratory in terms 52
of compactive effort and OBC
LIST OF FIGURES
FIGURE NO. TITLE PAGE
1.1 Marshall Impact Hammer 02
1.2 Kneading Compactor 03
1.3 Gyratory Compactor 04
3.1 Flow diagram for laboratory analysis process 26
3.2 Sieve arrangements 29
3.3 Cone test to determine SSD. 34
3.4 Marshall test procedure 39
4.1 OBC v/s NMAS 53
4.2 OBC comparison 53
LIST OF APPENDICES
APPENDIX TITLE PAGE
A Aggregate gradation for laboratory mix design 63
B Marshall Test Results 68
C Results of Marshall Mix Design with Gyratory Compactor 77
D Superpave Mix Design 82
CHAPTER 1
INTRODUCTION
1.1 Introduction:
Compaction of Asphalt concrete mixtures in flexible pavements plays a major
role in the performance of these pavements. Mix properties, such as density and air
voids are highly dependent on the degree and the method of compaction. These
properties in turn affect pavement performance indicators, such as rutting and fatigue
cracking.
The difference between laboratory compaction methods is not only the result
of the evaluation procedure but is also the consequence of the compaction technique
used. The goal of a mix design procedure is to combine aggregates and a binder in a
proportion that is able to satisfy a desired level of performance. Realistic procedures
for evaluating the strength of bituminous mixtures is therefore quite important. There
are several factors that affect the strength of bituminous mixtures; one of them is the
method of forming a realistic test specimen in the laboratory that represents the
structure of the paving mixture when it is placed in the field. Duplicating the
composition of a field mixture in the laboratory presents some problems, but they are
minor compared to producing in the laboratory a specimen of the mixture that truly
represents the mixture as it exists in the field (Blankenship et al.. 1994).
The quality of an asphalt pavement depends largely on the quality of the
construction techniques used. An asphalt mix might be well designed and well
produced, but if it is placed in the road in an improper way, the pavement
performance will be poor. Therefore next to mix design, degree of compaction must
be considered the main quality parameters of a laid asphalt mixture. A well designed
and well produced mixture performs better, has better durability, and has better
mechanical properties when it is well compacted.
1.2 Laboratory compaction
The objective behind laboratory compation is to simulate the ultimate
compaction achieved in and asphalt pavement. Historically three laboratory
compaction methods have been used in asphalt laboratory mix design and those are:
1.2.1 Compaction by Impact
Figure 1.1: Marshall Impact Hammer
This is oldest technique in laboratory compaction. In the beginning of the 20th
century, Hubbard and Field used a Proctor hammer to compact asphalt mixtures.
This hammer was borrowed from the Geotechnical field. In the 1930s. Bruce
Marshall adopted the Hubbard-Field method and began developing the method,
which bears his name. The only difference was that he used a compactor face equal
to the mould diameter. The number of blows applied to each face of the specimen
was set to be 35, 50 or 75 depending upon the anticipated traffic volume. The higher
the volume of traffic, the greater the number of blows. This is the most common mix
design method used today. The Marshall Mix design or a variation thereof has been
adopted by 75 percent of the highway agencies in the U.S. However. Consuegra et al.
(1989) concluded that the Marshall hammer least simulates the actual field
conditions that will be encountered by pavement during its service life.
1.2.2 Kneading Compaction
Figure 1.2: Kneading Compactor
In the 1930s and 1940s F.N. Hveem developed a mix design method referred
to as kneading compaction. This method was different from the Marshall Mix design
method. The compacting force in this compactor is applied through a roughly
triangular-shaped foot, which partially covers the specimen face. To effect
compaction, tamps are uniformly applied on the specimen face. The traffic volume is
represented by the pressure of tamps. More tamps and higher lamp pressure
simulates mixtures subjected to high traffic volume. This type of compaction is used
primarily in pans of the Western United Stales, but used infrequently elsewhere.
1.2.3 Gyratory Compaction
Figure 1.3: Gyratory Compactor
Gyratory compaction was developed in the 1930s in Texas (Blankenship et
al.. 1994). This compaction produces a kneading action on the specimen by gyrating
the specimen through a horizontal angle. The range of the angle varies from 1.00 to
6.00 degrees. During the process of compaction a vertical load is applied while
gyrating the mould in a back-and- forth motion.
Development and use of compaction via gyratory action has continued by the
U.S Army Corps of Engineers and by the Central Laboratory for Bridges and Roads
(LCPC) in France (Blankenship. 1994). Such development has focused on the
application of the principle of gyratory movement and oil the establishment of a new
method of asphalt mix design to simulate service under extreme traffic conditions.
The use of this compactor became commonplace in the early 1960s; however, the
costly gyratory testing machine has achieved little acceptance as a routine mix design
tool and is used mainly as a research tool. The LCPC had evaluated parameters
affecting gyratory compaction and had finalized a gyratory protocol, where three
major variables had been studied: angle of gyration, speed of rotation, and vertical
pressure. Today, the gyratory compaction method is commonly used in the mix
design process in France. A major difference between the French design process and
North American design is that in the French design the compactor simulates density
at the end of construction instead of during service.
In 1993, The SHRP introduced a trademarked "Superpave" laboratory
mix design procedure based on a gyratory compaction device (Cominsky et al.1994).
This laboratory design procedure was deemed to be appropriate for original and/or
recycled hot mixtures and with and/or without modified binders. The Superpave mix
design method recommended three hierarchical levels of design, namely Level 1, 2
and 3 based on anticipated traffic volume. Each design level also took into account
the influence of the site climatic conditions. However, in 1995 the SHRP decided to
employ the Level 1 design for all volumes of traffic (low, medium and high). The
sophisticated and complex analytical techniques and costly test equipment for levels
2 and 3 design did not lend themselves to usage in a Hot Mix Asphalt production
facility. The HMA industry concurred with this decision and was of the opinion that
most pavements forming part of the National Highway System (NHS) would perform
well if designed using the concepts of the Superpave Level I mix design (Decker.
1995).
1.3 Problem statement
In developing countries like Malaysia the dramatic growth in vehicular traffic
have augmented axle loads and increased tire pressure on the pavements resulting in
rutting and cracking. Compaction of asphaltic concrete mixtures in flexible
pavements plays a major role in the performance of these pavements. Mix properties,
such as density and air voids are highly dependent on the degree and the method of
compaction. These properties in turn affect pavement performance indicators, such
as rutting and fatigue cracking.
1.4 Objectives
Objectives selected for this study were:
to compare HMA properties (density and air voids) of laboratory compacted
samples and ;
to examine co-relation between Marshall and gyratory laboratory compaction
methods.
1.5 Scope of Study
The key points aimed to maintain the scope during the study were
compaction of asphalt concrete mixes by Marshall and gyratory compaction methods
to evaluate HMA properties of the mix and to find some co-relations in HMA
properties between two laboratory compaction methods. Further more, to compare
the effect of different number of blows and different number of gyrations as
compactive efforts for ACW10, ACW14, ACW20 and ACB28 mix designs, as
performance of mixes in terms of density and air voids were observed according to
the serial tests.
The compaction methods used to evaluate HMA properties were Marshall
and superpave laboratory compaction methods. Standard mix design procedures were
differentiated on their method of compaction, which is assumed to simulate field
compaction. With the Marshall design methods, specimens are prepared by impact
compaction, while in the superpave design method, specimens are fabricated by
gyrations. This type of compaction was developed to produce realistic specimens
which compared favorably to in-service mixtures after traffic compaction. The
gyratory compaction technique was introduced to simulate the increasing loads and
tire pressures of vehicles operating on the pavement. Prior to this compaction
technique, it was not possible to achieve a realistic field density in laboratory
specimens. Recently, the Strategic Highway Research Program (SHRP) adopted,
with some modification, the gyratory compaction procedure in asphalt mix design.
1.6 Purpose of study
The goal of this study was to compare and evaluate laboratory compaction
methods that are widely used and/or resemble as closely as possible. The objective of
this study was to select a compaction technique that is able to achieve material and
engineering properties (such as air voids and density), which are similar to those of
material placed in the field using standard compaction practices. The selected
compaction techniques for this study were Marshall Automatic Impact Compaction
and Gyratory Compaction. Required aggregates were collected from the Malaysian
Rock Products (MRP) quarry, other material required and Laboratory tests facilities
were provided by Transportation Laboratory University Technology Malaysia to
prepare samples for comparison and evaluation. Procedure as described by the
National Asphalt Paving Association (NAPA) to determine the optimum bitumen
content (OBC) was selected. The asphalt content percentage, which corresponds to
the 4% air void at VTM, is determined. The 4% is the specification of median air
void content.
CHAPTER II
LITRATURE REVIEW
2.1 Introduction
Increased traffic, axle loads and tire pressures, coupled with limited financ
resources have resulted in commonly occurring overstressed asphalt pavemen
These conditions have forced asphalt engineers and researchers to reconsider t
current mix design approaches.
The proper selection of the aggregates and the asphalt binder can impro
pavement performance, depending upon the environmental and traffic conditions
which the pavement is exposed. However, the asphalt concrete mix will not perfo
as required if the proper compaction procedure is not followed.
The most common mix design methods used are the Marshall, Hveem, a
gyratory methods, but the Marshall laboratory mix design method is leading as 70
of the agencies throughout the world are still using this method and the introducti
of the Superpave laboratory mix design procedure, based on a gyratory compacti
device, has given rise to calls for replacing the traditional Marshall mix desi
method by that of Superpave. Researchers and engineers have worked on identifyi
the best properties of these mix design methods and have spent time validating t
attributes of each method.
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The validity of performance in the field and the cost of the equipment for the
two mix design methods have to be taken into account in selecting whether a
Marshall or a gyratory compaction device should be used in future asphalt concrete
mix design
The following section presents a literature review of laboratory compaction;
Marshall and Gyratory mix design, and binder use.
2.2 Laboratory Compaction
In general, compaction of an asphalt concrete mixture is defined as "a stage
of construction, which transforms the mix from its very loose slate into a more
coherent mass, thereby permitting it to carry traffic loads… the efficiency of the
compactive effort will be a function of the internal resistance of the bituminous
concrete. This resistance includes aggregate interlock, friction resistance, and viscous
resistance" (Swanson et al.. 1996). If the resistance of the mix to compactive effort is
low then the pavement will he unable to carry traffic loads for any significant period
of lime.
Hughes(1989), defines compaction as ..."the process of reducing the air-void
content of an asphalt concrete mixture. It involves the packing and orientation of the
solid particles within a viscoelastic medium into a more dense and effective particle
arrangement. Ideally, this process takes place under construction conditions rather
than under traffic."
Compaction is one of the important factors that have been considered for
designing the asphalt pavement and constructing the road. Many studies had been
conducted to measure the performances of the asphalt pavement compactive effort
but it always led to some question that need to be addressed. This chapter will carry
out the previous studies according to the influences of compactive effort to the
pavement performance.
Compaction of asphaltic concrete mixtures in flexible pavements plays a
major role in the performance of these pavements. Mix properties, such as air voids
are highly dependent on the degree and the method of compaction. These properties,
in turn, affect pavement performance indicators, such as rutting and fatigue cracking.
Mix design procedures and specifications are usually derived from laboratory
experiments conducted on materials that are to be used in the field. Laboratory
conditions are less time consuming and relatively easy to control for these purposes.
However, laboratory tests should simulate to a high degree the conditions in the field.
In this context, laboratory compaction procedures should simulate compaction in the
field, not only in terms of density but also in terms of aggregate particle orientation.
A study on how compaction, measured by air voids, influences the
performance of dense asphalt concrete pavement surfaces. They found that a 1%
increase in air voids tends to produce approximately a 10% loss in pavement life.
The used base-course air void level was 7%, and the data were collected from 48
state highway agencies in the United States. The analysis in this study was done on
the basis of two performance indicators: fatigue cracking and aging.
A high degree of compaction improves the stiffness of asphaltic concrete
materials and hence improves the ability of the material to distribute traffic loads
more effectively over lower pavement layers and the soil foundation. Good
compaction with a target void of 4–7% also increases the resistance of asphaltic-
bound layers to deformation and improves their durability.
2.3 Factors affecting compaction
There are many factors affecting the degree of compaction of an asphaltic
bound material. These include material temperature, thickness of the laid materials
(lift thickness), binder content, and type and grading of the aggregates used in the
asphaltic concrete mixture.
A study shows the effect of compaction in terms of a number of factors and
rated these factors on the basis of the degree to which they contributed to the cause
of each pavement distress: permanent deformation; fatigue cracking; low-
temperature cracking; and moisture damage. It was concluded that several factors
(environmental conditions, lift thickness, mix properties, type of compaction
equipment, and roller operation) played a role in influencing pavement performance
indicators except in relation to low-temperature cracking.
As part of the Strategic Highway Research Program (SHRP) project A-003,
‘performance related to testing and measuring asphalt–aggregate interaction and
mixtures', three compaction methods were studied to determine the extent to which
the compaction method affects the fundamental mixture properties of importance to
pavement performance in-service. Two gyratory shear compactors, a kneading
compactor and a rolling-wheel compactor, were studied. A total of 16 asphalt–
aggregate mixtures were tested, and it was found that the method of compaction
affected the way test specimens respond to laboratory loading. Regarding resistance
to permanent deformation, the kneading compaction produced the most resistant
specimens. This was followed in order by rolling-wheel compaction and gyratory
compaction. Regarding mixture stiffness, the rolling-wheel compaction produced the
stiffest mixtures. This was followed in order by kneading compaction and gyratory
compaction. Among the studied compaction methods, the gyratory compaction
seemed to be the best in simulating field-compacted mixtures.
The gyratory testing machine is a combination of a kneading compactor and a
shear testing machine. It is a realistic simulator of the abrasion effects caused by
repetitive stress and inter-granular movement of the mass of material within a
flexible pavement structure. This method of compaction was developed to simulate
the increasing load and tire pressures of vehicles operating on flexible pavements. It
was standardized as ASTM D3387 to be used for guidance in selecting optimum
asphalt content and establishing density requirements, in addition to obtaining the
shear strength factor with regard to shear under load and strain conditions to be
adopted in a mix design.
Sigurjonsson and Ruth, used the gyratory testing machine to evaluate the
asphalt–aggregate mixtures of known performance in terms of their rutting
resistance. They concluded that the gyratory compaction machine produced mixtures
which were not sensitive to reasonable changes in binder content, gradation, and
mineral filler content. This key conclusion eliminated the need for multiple
parameter criteria, which can eventually simplify both design and quality control
processes. Recently, the Strategic Research Program (SHRP) adopted the use of the
gyratory compaction method in the SUPERPAVE mix design under SHRP
Designation M-002.
Consuergra et al.(1989) performed a combined field and laboratory study that
evaluated the ability of five compaction devices to simulate field compaction. The
compaction devices evaluated were selected on the basis of their availability and on
their uniqueness in mechanical manipulation of the mixture. The devices evaluated
were:
(a) the Texas Gyratory Compactor;
(b) the California Kneading Compactor;
(c) the Marshall Impact Hammer;
(d) the Mobile Steel Wheel Simulator; and
(e) the Arizona Vibratory Kneading Compactor.
The results of their study showed that the Texas Gyratory Compactor was
best in terms of its ability to produce compacted mixtures with engineering
properties similar to those produced in the field. The California Kneading Compactor
was ranked second on the basis of its ability to replicate field conditions. Neither the
Marshall Impact Hammer nor the Arizona Vibratory Kneading Compactor were
found to be very effective.
2.4 Asphalt Mix Design
This section reviews the literature pertaining to the laboratory and field
research performed on asphalt concrete mixes in order to evaluate present asphalt
mix design methods.
2.4.1 Mix Design Methods
The objective of an asphalt concrete mix design method is to determine the
proper proportions of aggregates and asphalt to produce an economical mix that
meets the Performance requirements of the pavement. Over the years, several mix
design methods have been developed and implemented by different agencies. This
review focuses on the Marshall and Superpave methods since they are currently used.
This section reviews the literature pertaining to the laboratory and field research
performed on asphalt concrete mixes in order to evaluate present asphalt mix design
methods.
2.4.2 Marshall Mix Design v/s Gyratory Mix Design
Button et al. (1994) compared four compaction devices (Texas gyratory
compactor, Exxon rolling wheel compactor. Elf linear kneading compactor and
Marshall hammer) to determine which of them would most closely simulate actual
field compaction. The study was limited lo dense-graded mixtures showed that
specimens compacted via gyratory compactor most often simulated pavement cores.
This occurred in 73% of the performed tests. The Marshall compactor gave the least
probability of producing specimens simulating the pavement cores (in 50 % of test
performed). However, the difference between field cores and the specimens produced
in the laboratory by the four-compaction methods were relatively small when all the
test results or each method are evaluated as a whole.
Similarly, Von Quintus et al. (1991) described the effect of five different
laboratory compactors (Texas gyratory compactor, Rolling wheel compactor.
Kneading compactor, Arizona vibratory/kneading compactor, and standard Marshall
hammer) on the selected properties of the compacted mixtures. Field cores and
specimens compacted in the laboratory were tested for indirect tensile strength
(ITS), strain at failure, resilient modulus and creep and their aggregate particle
orientation was evaluated. The authors compared the similarity between laboratory
compaction and field compaction techniques. Their results are given in Table 2.1
(Von Quimus. 1991).
To facilitate the ranking of compaction devices, three procedures were used
to define which compaction device more closely simulated the engineering properties
of field cores. The ranking of the compactors by order of performance: the Texas
Gyratory compactor followed by Rolling Wheel compactor, California Kneading
compactor, Arizona Vibratory / Kneading compactor, and lastly, the standard
Marshall hammer.
Another study to evaluate the ability of five compaction devices to simulate
field compaction is described in Consuegra's et al.. (1989). These devices are the
mobile Steel wheel simulator, the Texas gyratory compactor, the California kneading
compactor, the Marshall Impact hammer, and the Arizona vibratory /kneading
compactor. The ability of these compaction devices to simulate field compaction is
based on the similarity between mechanical properties such as resilient moduli,
indirect tensile strength and strains at failure and tensile creep data of laboratory-
compacted specimens and field cores.
Table 2.1: Summary of Engineering Properties Comparisons S.No Compaction devices Percentage of Indifference in properties between
laboratory-compacted specimens and field cores
1 Texas Gyratory 63
2 Rolling Wheel 49
3 Kneading Compactor 52
4 Arizona Vibratory/ Kneading 41
5 Standard Marshall hammer 35
The mixture properties were evaluated based on ITS test at 5, 25 and 40 0C,
creep load strains at 25 0C and 40 0C with a loading time of 300 sec. and slopes of
creep curve at 250C and 40 0C.
While highest level of similar properties between laboratory -compacted
specimens and field the Texas gyratory compactor demonstrated cores. The
Marshall impact hammer ranked as the least effective. This was attributed to the
lack of a kneading motion by the Marshall Impact hammer. The authors concluded
that the Marshall hammer is the least able lo simulate any of the construction and
traffic compaction methods.
AI-Sanad (1984) investigated the effect of various laboratory compaction
methods on three different mixtures. The compaction methods were the Marshall
hammer, the kneading compactor, and the gyratory compactor. The Marshall
hammer produced high impact stress energy and resulted in an excellent orientation
of aggregates. Nevertheless, the specimens compacted with this compactor in the
laboratory gave different stress-strain curves than pavement cores having the same
density and asphalt content. He concluded that the compaction method affects the
stability. The kneading compactor produced specimens with greater stability than the
Marshall hammer and the gyratory compactor. The specimens compacted by the
Marshall hammer and the gyratory compactor have approximately the same stability,
but the level of air voids in cores compacted by the Marshall method was higher than
that compacted by the gyratory method.
Murfee and Manzione (1991) analyzed the plastic behaviour of Marshall and
gyratory mixes in order 10 determine if the asphalt mixtures are appropriate for
fighter aircraft taxiways. The flexible and composite pavement test sections were
prepared to study rutting of asphalt pavements under high tire inflation pressures.
Late-model aircraft such as F-16s which require tire inflation pressures in the order
of 310 psi were considered for this study.
2.4.3 Gyratory Compactor v/s Marshall Compactor
Harman et al. (1995), Investigated the applicability of the Superpave gyratory
compactor (SGC) to Held management of the production process. Based on
production results, tolerance limits were established for SGC acceptance parameters.
The Federal Highway Administration - Office of Technology Applications (FHWA-
OTA) recommended that these parameters be asphalt binder content, voids in total
mix. and voids in mineral aggregate. The volumetric properties of SGC specimens
were compared to those of the Marshall specimens in Harman's paper.
As the cost of an SGC is approximately seven times that of a Marshall
compactor and as there are relatively few units available for design and field quality
control, an effective solution to this conundrum would be to utilize the Marshall
hammer lo field control the quality of Superpave mixes. The collected data indicated
that there is no correlation between the SGC and the Marshall compactor. If the voids
in specimens compacted with the SGC' are compared to those compacted with the
Marshall compactor, it is obvious that me SGC produces a compactive effort greater
than that with Marshall. There is no fixed correction factor or constant which would
permit the estimation of gyratory volumetric based on Marshall specimens. In other
words, the data from Marshall-compacted specimens is not transformable for use in
volumetric comparisons. In addition, the SGC and Marshall Specimen volumetric
react differently to changes in asphalt cement content.
The authors emphasized the impracticality of adjusting a Superpave-designed
mix based on Marshall Held data. They are of the opinion that surrogate compactors
should not be employed in the field management of Superpave mixes
Hafez and witezak (1995) compared the design asphalt contents results
obtained by the Marshall procedure to the Superpave gyratory Level 1 procedure.
The Superpave designs were conducted to adequately sustain a traffic volume
comparable to traffic represented by 75 blows in the Marshall procedure. Five mix
groups and three climatic regions, from cool to warm were evaluated. They
concluded that the difference in asphalt content within any specific mix type was not
sensitive to the air void le\el that was selected in developing the design value. The
design range of the air voids was from 3-0°o to 5.0%. The Superpave climatic
regional changes dictated an increase of approximately 1.0% of additional asphalt
required per climatic region in the Level 1 mix design as compared to a Marshall-
designed mix. Furthermore, the design asphalt contents for the standard and wet
process (manufacturer-pre-blended) asphalt rubber mixes were comparable in the
Marshall and the Superpave specimens in warm climatic regions. Conversely, for wet
process (plant-blended) asphalt rubber mixes. Marshall mixes required a 0.5°o to
0.8% asphalt content less than the Superpave-designed mixes if polymer-modified
asphalt cement was used to meet equivalent traffic and climatic conditions.
Andersen el al. (1995), described the results of the quality control evaluation
of asphalt mixtures with equipment developed in the SHRP. They focused on the
feasibility of using SGC for Held quality assurance. The four asphalt contents used in
the evaluation of the SGC were 4.0, 4.5, 5.0, and 5.5 % in mixes. The Marshall Mix
design method was evaluated only at 4.5°o design asphalt content. Alt specimens
compacted with the SGC were prepared with approximately 5.000 gm of the mixture
and subjected to 204 gyrations. T he 4.5% specimens compacted with (he Marshall
Compactor comprised approximately 1200 gm of the mixture with the standard 75
blows. The research concentrated on the control of the mixture components (asphalt
content, aggregate gradation) and the mixture volumetric and densification properties
(percentage of air voids).
It was concluded that there was a close correlation between the percentage of
voids in mineral aggregate (VMA) and the percent voids in filled asphalt (VFA) with
(lie percentage of air voids established for both SGC and Marshall specimens. The
percentage VFA was generally higher than the design values. Both the SGC and
Marshall procedures were sensitive to changes in asphalt content and somewhat less
significantly, to gradation- In the field specimens the average difference in air voids
was 0.3% for the two SGC specimens and 0.6% for the three Marshall specimens.
For the specimens designed in the laboratory, the average difference in air voids was
0.1% for the three SGC specimens, and 0.6% for the three Marshall specimens. One
may conclude that the SGC procedure produces specimens with less variance within
the group. This could be attributed to the compaction process and might also be due
to the larger specimen size in the SGC procedure.
The authors concluded that the SGC procedure appeared to be at least as good
a tool for a field control as the Marshall procedure is. The lesser variability resulting
from the SGC would in still greater confidence in the test results.
Harman et. al.. (1995) evaluated the use of the SGC in the field management
process. They inspected four different paving projects. The designed mix was
specimend directly from the delivery vehicles and sent to the FHWA-OTA mobile
laboratory for compaction by a prototype SGC. The quality level of SGC and
standard Marshall test results were statistically analyzed. A volumetric property
analysis was performed to compare the SGC specimens, and the Marshall specimens.
The three control parameters utilized were asphalt binder content. VTM and
VMA, Study outputs dictated that production tolerances should be ±0.4 % for asphalt
cement (AC) ± 1.1 % VMA. Thus the V, (air voids) and VMA were set lower for
SGC mixes than those of Marshall mixes (±1.5 % for Va and VMA). The greater
compactive effort by the SGC resulted in lesser VTA's and VMA's for all four study
locations. The SGC specimens had on average a 1.7% lower V, and a 1.6% lower
VMA than the Marshall specimens. It became obvious that specimens with lower
void levels would offer less variability and therefore lower standard deviations
during production. To come up with conclusions for compaction comparison (SGC
versus a surrogate Marshall Compactor) the authors considered the following facts:
the cost of SGC (7 times more than the Marshall compactor), the relatively few
SGC's currently available for design and field quality control, and the widespread
availability of the Marshall hammer. However the data obtained from these four
study locations indicated the following:
no correlation of data between the SGC and Marshall compactor
the SGC produces more compactive effort
the difference in SGC / Marshall compactive effort is not consistent
among the four mixes.
it is not possible to establish a fixed correlation factor in order to estimate
volumetric through the use of Marshall compactor.
Based on these results, the authors indicated that the determination of
appropriate tolerance limits based on local production which lakes into account the
regional difference should be within the purview of each U.S. slate highway agency.
they concluded that a Marshall compactor should not be used as a surrogate for field
verification of Superpave designed mixes. The primary reason is that the Marshall
Compactor compacts aggregate and asphalt differently from the SGC'. As a result.
Marshall Compactors are not recommended for use in the field management of
Superpave mixes.
2.5 Pavement Performance
Bahia and Anderson (1995) defined four temperature zones wherein the
asphalt binder influences the pavement performance. The first zone is. that where the
temperature is higher than l00 0C. Most asphalt binders become totally viscous and
behave like Newtonian fluids at temperatures above 100 0C. The malleability or
workability of asphalt during the mixing and construction of HMA can thus be
adequately measured by its viscosity. The second zone is that of temperatures
between 45 0C and 85 0C. This is the highest range of temperature for pavement in
service. The main failure in this zone is rutting. The objective is to achieve a high
resistance to permanent deformation and the low relative elasticity of asphalt
reflecting a more elastic component of the total deformation.
Asphalts in the intermediate temperature zone between 0 0C and 45 0C are
commonly harder and more elastic than asphalts in higher temperature zones. The
primary failure mode is fatigue damage and is caused by repeated loading: cycles. A
softer and more elastic material offers better resistance to fatigue damage. This is due
to lower stress for a given deformation which results in an easy asphalt recovery
from its preloading conditions.
The fourth temperature zone is the low -temperature zone under 0’C. The
main failure mode here is thermal cracking brought about by thermal cooling and
resultant shrinkage. During the cooling process, asphalt stiffness increases
continuously with the corresponding' greater stresses for a given shrinkage strain.
2.6 Conclusions of the Literature Review
The preceding review of available literature leads to make the following
conclusions:
Marshall and gyratory Compaction:
The orientation of the aggregates is important in order to develop mixture
strength through stone-on-stone contact.
The method of compaction affects the stability of specimens,
Specimens compacted with the gyratory compactor exhibited similar
properties to that of field core specimens.
The Marshall compactor gives the least probability of producing specimens
similar to pavement cores.
Air voids are greater in specimens compacted by Marshall when compared
with specimens compacted by a gyratory device.
The rotational compaction pressure of the gyratory compactor permits the
preparation of customized densities to meet the requested compactive effort.
There is close correlation between pavement voids and voids obtained in the
laboratory with the gyratory unit. A low degree of correlation characterizes
the 75-blow Marshall compactive effort.
Test equipment for Superpave mix design is approximately 7 limes more
costly than the standard Marshall compactor - a net inhibiting factor in terms
of increasing the use of the Superpave design and associated test equipment
SGC and Marshall Specimen volumetric react differently too change in
asphalt binder content. There is no consistent correlation between these two
compactors
Aggregates and asphalt contents are compacted differently in the Marshall
compactor than in SGC. The re-orientation of aggregates during gyratory
compaction results in specimens that are much denser and having a lower
VMA than those compacted by Marshall. Therefore the Marshall resemble
gyratory compactor should not be used as a surrogate for the gyratory
compactor in the field management of Superpave mixes.
Mixes designed with the SGC cannot he tested and controlled in the field
using the Marshall because of differences in VMA (voids in mineral
aggregates).
Each locality or region has to evaluate material being used for mix design
with an understanding of historical performance.
Additional studies are necessary in order to identity and validate the best
laboratory compaction method.
Further evaluation of the gyratory compactor as a design tool for asphalt
mixes is needed in order to supplement the Marshall design. The SGC
method appears lo be an effective field control tool and at least as good as the
Marshall method in one study.
The conclusion of this section is that compaction is one of the most important
factors in designing and constructing asphalt pavements. Engineers working in the
field of transportation should focus on evaluating and developing current compaction
equipment from the point of view of cost and applicability based on post-
construction performance.
CHAPTER III
METHODOLOGY
3.1 Introduction
The main objective of this research was to compare the two laboratory
compaction techniques and to examine correlation between these two methods,
which are Marshall and gyratory. In other words this research was carried out to
identify under which condition both laboratory compaction method give same
results. To conduct this comparison between these two compaction methods, the
specimen were prepared according to some standards, in this case samples were
prepared and tested according the JKR/SPJ/2005 and NAPA as a guide line to attain
the laboratory works and materials to fulfill the Malaysian Road Works
circumstances. ACW10, ACW14, ACW20 and ACB28 were used as a gradation
limit for asphaltic concrete mixtures. Table 3.1and Table 3.2 shows the appropriate
envelops for gradation limits of aggregates and asphalt concrete ranges stated by
JKR, used in this project respectively. Several of the tests accomplished in Highway
& Transportation Laboratory, University Technology Malaysia.
3.2 Operational Framework
It is known that, control over quality of compaction focuses on air voids and
density. In this case it is decided to use density as the material property to control the
compaction quality. Based on the density this project was divided in to different
stages to find some correlation between Marshall and Gyratory laboratory
compaction methods.
The laboratory work consisted of two series of tests with the first being tests
done prior to mixing and second series being the tests done on prepared specimens.
The tests conducted for the first series were sieve analysis, and determination of
specific gravity for aggregate (coarse and fine). The aggregate obtained from the
quarry was sieve to separate the aggregate into different sizes for later use. Washed
sieve analysis was done to determine the percentage of dust and silt-clay material in
order to check the need for filler material. Aggregate blending satisfying the JKR
gradation limits are to be used. Subsequently, the process of specific gravity
determination for coarse and fine aggregate takes place.
The second series involved the mix design. A total of 128 specimens
(Marshall and Superpave) were prepared. The sample preparation incorporates
specifying the mixing and compaction temperatures, sample shot-term aging, and
determining the optimum bitumen content. The Rice method was used in
determining the maximum theoretical specific gravity, and water displacement
method was used in determining the bulk specific gravity. The general procedures
for laboratory works are illustrated in Figure 3.1.
Since density was taken as the control factor and it was not possible to
regulate density of Marshall compacted specimens unlike gyratory
compacted specimens, so Marshall compaction was carried first.
To accomplish above task mixes were prepared based on Marshall
Laboratory mix design method. ACW10, ACW14, ACW20 and ACB28
mixes were prepared based on 75-blows (heavy traffic).
Density at OBC was obtained after using Marshall Compactor as
laboratory compactive effort
Same density was achieved by gyratory compactive effort using same mix
designed under Marshall laboratory mix design method and the equivalent
number of gyration required to obtain the density were observed.
Based on equivalent number of gyrations required to achieve the same
density as of Marshall compacted samples, mixes were prepared using
Superpave Mix design method.
Differences between two laboratory compaction methods in terms of
density and optimum bitumen contest were observed.
Determination of Bulk Specific Gravity
Determination of Maximum Theoretical Specific Gravity
Detfor
Dete
Mix design for AC10, AC14, AC20, and AC28
Determination of specific gravity for coarse and fine aggregate
Aggregate blending to obtain the desired gradation that is well within the gradation
limits
Washed sieve analysis to determine the percentage of dust and silt-clay material
Dry sieve analysis to distribute the aggregates into different sizes
Figure 3.1: F
Determination of the Density
ermination of Equivalent gyrations superpave to obtain same density
Analyses and Discussion
rmination of OBC using superpave
low diagram for laboratory analysis process
3.3 Preparation of Materials for Mix
Materials used for this study were aggregate, bituminous binder, filler, and
anti-stripping agent. All materials were prepared in accordance to the Standard
Specification for Road works published by JKR (JKR/SPJ/rev2005).
3.3.1 Aggregates
According to JKR/SPJ/rev2005, aggregate for asphaltic concrete were
mixture of coarse and fine aggregates, and mineral filler.
Course aggregates
The coarse aggregate must conform to the requirements –the Los Angeles
Abrasion Value shall not be more than 25% (ASTM C 131), the weighted average
loss of weight in the magnesium sulphate soundness test of 5 cycles shall not be
more than 18% (AASHTO T 104), flakiness index shall not be more than 25%
(MS30), water absorption shall not be more than 2% (MS30), and polished stone
value shall not be less than 40 (MS30).
Fine aggregates
Fine aggregate normally consists of quarry dusts. Fine aggregate must
conform to the requirements – sand equivalent of aggregate fraction passing the
4.75mm sieve shall be not less than 45% (ASTM D 2419), fine aggregate angularity
shall not be less than 45% (ASTM C 1252), the Methylene Blue value shall be not
more than 10mg/g (Ohio Department of Transportation Standard Test Method), the
weighted average loss of weight in the magnesium sulphate soundness test of 5
cycles shall not be more than 18% (AASHTO T 104), and the water absorption shall
not be more than 2% (MS 30).
3.3.2 Bituminous Binder
Bituminous binder for asphaltic concrete was the bitumen of penetration
grade 80-100, which conforms to MS 124.
3.3.3 Mineral Filler
Mineral filler for this study was ordinary Portland cement. It must be
sufficiently dry and shall be essentially free from agglomerations. The coarse
aggregate, fine aggregate and mineral filler of the final gradation passing 75µm sieve
to bitumen, by weight shall be in the range of 0.6 to 1.2. The mineral filler will also
serve the purpose as an anti-stripping agent.
3.4 Sieve Analysis
There are two methods for determining aggregate gradation, i.e. dry sieve
analysis and washed-sieve analysis.
3.4.1 Dry Sieve Analysis
Dry sieve analysis was performed on aggregates obtain from quarry,
Malaysian Rock Product Sdn. Bhd. (MRP), Ulu Choh, Kulai, Johor. This test was
done to separate the aggregate into different sizes. Dry sieve analysis was in
accordance to ASTM C 136. Arrangement of different sive sizes used for aggregate
gradation is shown in Figure 3.2.
Figure 3.2: sieve arrangement
The apparatus used for dry sieve analysis were:
(i) Sieves with various sizes starting from 37.5mm to pan;
(ii) Mechanical Sieve Shaker; and
(iii) Balance with the accuracy of 0.5 g.
The procedures for dry sieve analysis was as follow:
(i) The sieves were arranged in order of decreasing size of opening from
top to bottom on the sieve shaker.
(ii) Placing of aggregate was performed on the top sieve and turn on the
shaker to start the sieving.
(iii) Aggregate that have been sieved was separated according to the size.
(iv) For mixing, total aggregate of different sizes as designed was
weighed.
3.4.2 Washed Sieve Analysis
Washed sieve analysis was done to determine the amount of dust and silt-clay
coated on aggregates. It was used to determine the total filler needed for the
particular mix. Washed sieve analysis was performed in accordance to ASTM C 117
and AASHTO T 27.
The apparatus used for washed sieve analysis were:
(i) Sieve size of 0.075mm;
(ii) Container;
(iii) An oven capable of maintaining a uniform temperature of 110±5°C;
and
(iv) Balance with the accuracy of 0.1g.
The procedures for washed sieve analysis was as follows:
(i) The aggregate samples will be weighed before being placed in the
container.
(ii) Fill the container with water until all the aggregates are submerge.
Thoroughly wash the samples to remove the dust and silt-clay
material and to bring the particles finer than the 0.075mm into
suspension.
(iii) Carefully, pour the sample onto the 0.075mm sieve to separate the
dust and the aggregate.
(iv) Repeat steps (ii) and (iii) until the water is clear to ensure that all the
dust and silt-clay material are thoroughly removed.
(v) Dry the washed sample in an oven at a temperature of 110 ± 5°C for
24 hours.
(vi) Weigh the sample after 24 hours and the percentage of material finer
than 0.075mm is calculated as follow:
Percentage of Material Finer than 0.075mm = 100×−A
BA
Where,
A = Original dry mass of sample, g
B = Dry mass of sample after washing, g
3.5 Aggregate Blending
The aggregate blending was used to determine the proportion of aggregates
needed for a specified mix. There were few steps involved, namely gradation
analysis, blending, and specific gravity determination. However, since the
aggregates were sieved earlier into individual size, the gradation process was
ignored.
Aggregate blending involved the process of proportioning the aggregates to
obtain the desired gradation that were well within the gradation limits. The gradation
limits for the mixes prepared were as specified by JKR/SPJ/rev2005 and are shown
in Table 3.1. For this study, the mixes prepared were ACW10, ACW14, ACW20,
and ACB28. The mixes combined coarse aggregates, fine aggregates, and mineral
filler. A smooth curve within the appropriate gradation envelope is desired.
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry (SSD) AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. % Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. by wt. c-e f SGbit SG(eff)agg
of Agg. of MIX.5.00 1206.6 1200.8 669.5 537.1 2.236
ASPHALTIC CONCRETE WEARING COURSE (ACW14)2.6141.03 DATE: 28th July 2006
80/100 PENMRPLaboratory Mix
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. % Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. by wt. c-e f SGbit SGag
of Agg. of MIX.4.50 1193.5 1181.6 661.6 531.9 2.221
ASPHALTIC CONCRETE WEARING COURSE (ACW20)2.6151.03 DATE: 2nd August 2006
80/100 PENMRPLaboratory Mix
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. % Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. by wt. c-e f SGbit SGag
of Agg. of MIX.4.50 1211.2 1207.8 690.8 520.4 2.321
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry (SSD) AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. % Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. by wt. c-e f SGbit SG(eff)agg
of Agg. of MIX.3.50 1201.3 1193.1 686.8 514.5 2.319
Results of Marshall Mix Design with Gyratory Compactor for ACW10, ACW14, ACW20 &
ACB28 Mixes
ASPHALTIC CONCRETE WEARING COURSE (ACW10)2.62361.03 DATE: 7th August 2006
80/100 PENMRPLaboratory Mix
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. c-e f SGbit SGag
of Agg.35.00 6.42 4667.1 4685.0 2560.2 2106.9 2.224
ASPHALTIC CONCRETE WEARING COURSE (ACW14)2.6141.03 DATE: 9th August 2006
80/100 PENMRPLaboratoyr Mix
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. c-e f SGbit SGag
of Agg.35.00 5.80 4689.7 4656.4 2576.5 2113.2 2.203
ASPHALTIC CONCRETE WEARING COURSE (ACW20)2.61501.03 DATE: 11th August 200
80/100 PENMRPLaboratory Mix
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. c-e f SGbit SGag
of Agg.50.00 4.90 4665.5 4654.5 2658.4 2007.1 2.319
ASPHALTIC CONCRETE WEARING COURSE (ACB28)2.6111.03 DATE: 16th August 2006
80/100 PENMRPLaboratory Mix
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. c-e f SGbit SGag
of Agg.40.00 4.80 4724.9 4685.8 2648.7 2076.2 2.257
Results of Superpave Mix Design for ACW10, ACW14, ACW20 & ACB28
ASPHALTIC CONCRETE WEARING COURSE (ACW10)2.6241.03 DATE: 4th September 2006
80/100 PENMRPLaboratory Mix
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. % Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. by wt. c-e f SGbit SGag
of Agg. of MIX.5.50 4607.4 4571.8 2535.2 2072.2 2.206
ASPHALTIC CONCRETE WEARING COURSE (ACW14)2.6141.03 DATE: 8th September 2006
80/100 PENMRPLABORATORY MIX
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. % Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. by wt. c-e f SGbit SGag
of Agg. of MIX.5.00 4609.7 4589.1 2602.5 2007.2 2.286
ASPHALTIC CONCRETE WEARING COURSE (ACW20)2.6151.03 DATE: 21st September 2006
80/100 PENMRPLABORATORY MIX
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. % Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. by wt. c-e f SGbit SGag
of Agg. of MIX.4.00 4550.9 4513.3 2588.0 1962.9 2.299
ASPHALTIC CONCRETE WEARING COURSE (ACB28)2.6111.03 DATE: 22nd September 2006
80/100 PENMRPLABORATORY MIX
% BIT % BIT. WEIGHT-gm BULK SPEC. GRAV. VOLUME - % TOTAL VOIDS - % SPEC. SPEC. Saturated IN IN VOL. MAX. FILLED TOTALNO. NO. surface dry AIR WATER cc. BULK THEOR. BIT AGG. VOIDS AGG. (BIT) MIX
a b c d e f g h i j k l m n
% Bit. % Bit. d b x g (100-b)g 100-i-j 100-j 100(i/l) 100-(100g/h)by wt. by wt. c-e f SGbit SGag
of Agg. of MIX.4.00 4600.2 4565.3 2623.2 1977.0 2.309