Dr.Vilas Deshmukh

Dr.Vilas Deshmukh

Sunday, July 17, 2011

grouted macadam bsuccessful technology for rehabilitationn of bituminous roads

Grouted Macadam: Successful Technology for rehabilitation of bituminous roads

V.V. Deshmukh,

Abstract

Despite the well-known disadvantages of bituminous roads it continues to be the most widely used option. In this research paper the challenge of building the most vital infrastructure of India has been addressed by ACC-RCD through the development of a technology called Grouted Macadam which meets the requirements (economic, technical and life cycle cost) better than the bituminous option. The Grouted Macadam is a composite which combines the flexibility of bituminous material with performance benefits of cementitious material. The high strength cement based grout is poured in the voids of coated aggregate layer or a high performance flexible concrete mix is prepared and laid as a pavement course.

Some of the important properties like Abrasion resistance, Marshall stability , Air voidage, Stiffness modulus and resistance to fuel spills were studied and compared with conventional bituminous pavement. It is observed that Grouted Macadam has higher stiffness modulus, lower temperature sensitivity, improved fatigue performance. These properties are used to custom design pavement structures that are comparable or better than conventional bituminous pavement.

The use of Grouted Macadam as a wearing course material in a flexible pavement construction has resulted in extended life compared to construction incorporating conventional bituminous materials. It has been extensively field tried and has gained wide market acceptance among several public/private sector organizations.

The Grouted Macadam technology offers a novel cost effective alternative in the field of road making and has the potential to significantly contribute to the country’s infrastructural needs

1 INTRODUCTION

India has a total road network of 3.35 million KMs and only about 65000KMs (2%) are the national highways which carry 40% of the traffic. Only about 2% of the total net work of roads are built with concrete as materials, the balance 98% are a combination of natural materials and bitumen.

The bituminous roads have well known disadvantages. The damage is mainly due to rutting, permanent shear strain and stiffening on account of aging. The rutting is the load-induced permanent deformation of a flexible pavement. Depending on the magnitude of the load and the relative strength of the pavement layers, permanent deformation can occur in the subgrade, the base, or the upper bituminous asphalt layers. Vulnerability of pavement layers to rutting varies at different times of the year. For example, rutting of bituminous asphalt layers is more common during summer and permanent deformation is more likely in sub-base during monsoon. The second important factor is the stress level in an individual pavement layer, which is a function of total pavement thickness and magnitude of the load. For example, application of a heavy load on a thin pavement over unstabilized sub-grade may induce excessive rutting in both the bituminous asphalt layer and the sub-grade.

An asphalt pavement that is subjected to repeated simple shear permanently deforms over time. This permanent deformation of pavement increase as the temperature of the pavement is increased. The effect is similar to what may occur at bus stops, where vehicles apply shear when they brake and shove the pavement.

Even in the absence of traffic, asphalt binder deteriorates. The stiffening of asphalt is seen to increase when the asphalt is merely exposed in a sunny, hot climate..

This research paper will illustrate how this challenge of building the most vital infrastructure of India has been addressed by the author working at ACC-RCD through the development of the technology called "Grouted Macadam" which uses high performance pavement concrete (HPPC) and meets the requirements (economy, technical and life cycle cost) better than the bituminous options.

"Grouted Macadam " consists of polymer coated aggregates with 25-30% voids in which is poured a cementitious grout. The grout is of improved cementitious binder which allows greater penetration of the void structure of polymer coated aggregate (PCA) and hence greater achievement of the theoretical packing density. The resulting material is typically used as a wearing course between 25mm and 75mm in thickness.

This type of grouted material offers the following benefits over a conventional bituminous material.

« High resistant to permanent deformation

« Fuel spill resistance

« Lower temperature susceptibility

« Higher Stiffness modulus.

1.1 Grouted Macadam Technology


« Grouted Macadam consists of an open graded coated aggregates with voids completely filled up with a special cement based grout. The grout is a dry, ready mixed which, when mixed with water, is a very light fluid material with high properties of penetration and internal cohesion.

« Grouted Macadam is laid jointless. The special coated aggregates provide the flexibility and the grout, with its characteristic dense micro structure, high wear resistance and high durability in aggressive environments.


STEP-1 STEP-3



The following methodology is used to lay grouted macadam in Bombay Municipal Corporation

The construction procedure is developed based on extensive research and data of field experience.

Grouted macadam: Methodology for application as flexible wearing course

Specifications

Wearing course for pavements

Scope of Work

The work shall consist of the general requirements for mixing and placing of coated aggregate filled with a grout. It includes the requirements for aggregate, binder, mixing at asphalt plant/ mixer, surface preparation, spreading and compacting of mix, mixing and pouring of grout

The composite shall consist entirely of aggregate coated with hot bitumen.. The voids in the finished mixture must comprise between 25 and 30 % of the total volume. The wearing course shall be laid in a thickness of 25 mm constructed of porous coated aggregates and filled with grout .

1. Coated Aggregate mixture: The mixture shall be as given in Table 1.

Table 1: Coated aggregate mix proportion

Material

Proportion

Bituminous material

3.8-4.0%

Aggregate

96-96.2 %

1. 1. Mix design shall conform with the requirement and the aggregates shall have a maximum size of 15 mm... After laying and rolling the Air Voids shall be in the range of 25-30%

2. Materials

2.1 Aggregate

The aggregates shall be chosen from basalt, granite, grit stone etc. The nominal size of the aggregates shall be as per requirement and in keeping

with the thickness of the pavement. The aggregates shall have a maximum size of 15 mm and minimum of 5mm. The property specs is attached.

Bituminous Material and Tack Coat

The bitumen shall be bitumen of 60/70 grade as per penetration test.

. The bitumen content in emulsion is measured as per IS 8887-1995.

2.2 Grouted macadam Grout:

The grout shall be made using Grouted macadam dry powder.It is cement based with mineral and chemical additives. The wet mixed grout shall be made at site in a mixer. The grout property specs is attached

3. Equipment

3.1 Mixing Plant

Aggregate coating shall be produced in a Hot Mix Asphalt mixing plant/ Mixer

3.2 Mix Transportation

Mixed bitumen coated aggregates from hot mix plant shall be transported to the site in tipper trucks constructed so as to prevent loss or undue segregation of materials after loading.

3.3 Rollers

Only steel-wheel rollers of 8-10 ton, max without vibration shall be used. Use of pneumatic rollers and vibratory rollers is prohibited.

3.4 Mixing and pouring of grout

The Grouted macadam grout shall be mixed in a mixer at brought to the site in wheel barrow/suitable equipments and laid.

4. Surface Preparation

The surface of the existing black top road shall be cleaned of all foreign material and broomed free of dust and all pot holes are repaired.

The tack coat of bitumen emulsion shall be applied at a rate of 0.5 kg/m2 as indicated in the specification.. The Tack Coat shall be evenly applied to the surface. The specs is attached

5. Mixing, Spreading and finishing

Mixing, spreading and finishing shall be a continuos operation. During the tack coating and the paving work only road roller necessary for the execution of the paving work shall be allowed on the coated aggregate course.

6. Installation of Grouted macadam grout

No traffic on the laid porous coated aggregate should be allowed before application of the grout. The porous aggregate course shall be free of any loose particles or other contaminants.

Mixing and pouring shall be a continuous operation. Not more than 3 hour shall elapse between water addition and the time of completion of grout laying.

Grouted macadam Composite

Property parameter

Method of test

Value

Compressive Strength(28days),Mpa on 4" core of composite

IS-516

4

Abrasion resistance in mm

IS-1237

4

Grouted macadam Grout

Property parameter

Method of test

Value

Density, kg/m3

IS 1528 -XII

1700-2000

Compressive strength, MPa, (3 days)

IS 516

15-20

Compressive strength,MPa, (28 days)

IS 516

50

The above does not constitute the specification of Grouted macadam. Depending on the project requirement, project specific specifications are drawn.

Specification for aggregate, bitumen content for coating and the grade of bitumen are given below:

In case of aggregate, the following is the sieve analysis

\

Sr.No.

IS sieve designation

% weight passing **

1

15-10 mm

80-100

2

10-5mm

0-20

3

0-5 mm

0-5

**The tolerance shall be +/- 5% by weight

Aggregate specification

Property parameter

Method of test

Value

Flakiness and elongation index

IS 2386

Max 30%

Aggregate Impact value

IS 2386(Part-4)

Max 30%

Los Angeles Abrasion value

IS 2386(Part-4)

Max 30%

Water absorption

IS 2386(Part-3)

Max 2%

Binder specification

Property parameter

Method of test

Value

Bitumen content in emulsion

IS-8887,1995

65%

Bitumen content in BM

IS-8887 1995

3.8-4.0%

Bitumen Grade

IS -1203-1978

60-70

Details of the jobs conducted at BMC and SMC are given below. The technology used is grouted macadam developed by the author in ACC-RCD.

ACCMARG JOBS

Month

Year

THK

AREA

REMARKS

Amount Rs.

Belapur rd/Out of Thn/BB

mm

Sq. meter

Panvel creek bridge

Sept.

2000

75

3390

5 No.Potholes repaired

528

Tolani Bridge

Nov.

2000

50

1019

O.K.

Nil

Mukund road

Dec./Jan.

2001

40

3652

Railway Bridge Work

Nil

Shapoorji-Lonawala

Dec./Jan.

2001

40

634

O.K.

Nil

MSRDC(Kon/Kalamboli)

Aug.

2001

40

9500

Gadhi river Bridge

Shirwane Road

Oct.

2001

40

4474

O.K.

Nil

L & T-Lonawala

Dec./Mar.

2002

30

65000

18.Nos.Potholes repaired

13520

Khambatki-Satara

May/Jun.

2002

40

6181

O.K.

Nil

MUMBAI-JOBS

HMP School-Andheri

Nov.

2000

40

4646

O.K.

Nil

Malad Subway

Jan.

2001

50

821

200 sqmt damaged

97884

US Club

Jan.

2001

40

1878

O.K.

Nil

LSN Ward

Mar./Sept.

2001

40

6018

O.K.

Nil

Sion Circle

Mar./Apr.

2001

50

5815

O.K.

Nil

S Ward

Apr.

2001

40

1327

13.Nos Potholes repaired

2636

Sion Station

Jun.

2001

25

711

25.Sqmt damage

6966

NM Joshi Marg

Sept.

2001

50

5812

5.Nos.potholes repaired

1200

Karani Road

Sept.

2001

40

2000

BMC replaced C. C.Road

Nil

Dadar Flyover

Oct.

2001

40

3003

2 No. potholes repaired

450

BPCL

Nov.

2001

50

2791

1 No.Pothole repaired

500

Mulund Container Yard

May

2002

35

3885

O.K.

Nil

NMMRDA

May/Apr.

2002/2003

40

6500

O.K.

Nil

Andheri Flyover

Aug.

2002

40

1793

Side edges Damaged

2700

Dahisar

Sept.

2002

40

1211

O.K.

Nil

Goregoan

Sept.

2002

40

1925

3 No. poteholes repaired

252

Borivali

Sept./Mar

2002/2003

40

1897

5 Nos.Potholes repaired

486

Tata Power

Oct./Nov.

2002

30

821

Polishing of laid ACCMarg

24000

Andheri Flyover-(E)

2003

40

1738

O.K.

Nil

M M R D A

Apr/MAY

2003

40

12035

O K.

Nil

Andheri Sub way

Feb /Mar

2003

40

3500

O.K.

Borivali

Mar/June

2003

40

6800

2 Nos.potholes repaired

225

Lonawala

Jan.

2003

40

7000

O.K.

Nil

OUT SIDE JOBS

Surat Ring road

Nov/ May

2002/03

30

92000

500sqmt repaired

85500

Tikariya Guriganj

Mar/ Jun

2003

40

11200

O.K.

Nil

Kyamur

Nov/ Jan

2002/03

40

25000

Some potholes repaired

5000

Total

305977

Sqmt

241847

This development is reported as research paper in NCCBM international seminar .The paper has received best paper award. The Copy has been attached here with. The product properties are studied by CRRI.The report is given below

2) LABORATORY TESTING OF Grouted Macadam

The performance evaluation of Grouted Macadam overlaid road sections was certified by the Central Road Research Institute (CRRI),New Delhi.. The team of CRRI scientist visited the Grouted Macadam site in Mumbai on Aug.2002.. The periodic observations included are the evaluated performance for skid resistance measurements using British Portable Skid Resistance Tester, surface texture depth measurements and extraction of pavement cores for determination of abrasion resistance, effect of water , petroleum products and temperature on Grouted Macadam.

2.1) THE SKID RESISTANCE MEASUREMENTS

Skid resistance measurements were under taken on the representative locations under dry and wet conditions of the pavement. Skid resistance values as obtained have been given in Table 1

Table 1

Location

Skid Resistance Values

Minimum Skid Resistance Requirements

Remarks

Dry condition

Wet condition

*Average

Range

*Average

Range

Inner lane

92

85 - 97

53

52 - 57

55

Good surface condition with coarse surface texture

Central lane

92

86 - 96

59

55 - 64

55

Good surface condition with medium to coarse surface texture

Outer lane

91

87 - 95

55

55 - 56

55

Good surface condition with medium to coarse surface texture

*Average based on ten observations.

2.2) TEXTURE DEPTH MEASUREMENTS.

Texture depth measurements were also made at representative locations where skid resistance was measured. The standard sand of known density was used .A known volume of fine sand of uniform particle size is poured on the road surface and the sand is spread until all the cavities are filled. The mean texture depth of the surface is calculated and the results are given in Table 2.

Table 2

Lane

Mean Texture Depth (mm)

Surface Texture Classification

Remarks

Range

Average

Coarse texture

Medium Texture

Fine Texture

Inner lane

0.37- 0.77

0.57

³0.50mm

0.50-.25mm

< 0.25 mm

Good surface condition with medium to coarse surface texture

Central lane

0.80- 1.50

1.15

³0.50 mm

0.50-.25mm

< 0.25 mm

Good surface condition with coarse surface texture

Outer lane

0.60- 0.92

0.74

³0.50 mm

0.50-.26mm

< 0.25 mm

Good surface condition with coarse surface texture

2.3) TRAFFIC VOLUME COUNTS

The daily traffic flow was assessed based on 24 hours volume count. Cars, buses, trucks, light goods and other commercial vehicles were recorded during the survey. Shown in Table 3

Table 3

24 Hours Traffic Volume Count at Sion Circle

Vehicle Type

Number of vehicles

Cars ( C )

50329

Buses ( B )

9566

Trucks ( T )

6271

*Other Goods Vehicles

5939

* Includes Tractors/Tractor trolleys etc.

2.4) ABRASION RESISTANCE

The cylindrical cores of 100mm diameter and 20-50 mm height were cut from representative locations. Core cutting was done using electrically operated (220v,1.8KW )BOSCH portable core cutting machine. These core samples were tested for abrasion as per IS 9284-1979.The abrasion test results of Grouted Macadam sample are given in table-4.

Table 4

Abrasion test results of Grouted Macadam sample

Sr. No.

Sample No.

Percent loss in weight

Tentative Suggested Maximum Value of Abrasion Loss(%)

1

11

0.25

(I) concrete pavement

2

13

0.21

(a)With mixed traffic including iron tyred traffic

= 0.16

3

14

0.21

( b) With pneumatic tyred traffic

= 0.24

4

15

0.29

(ii) Factory floors

= 0.16

Average

0.24

(iii) Dockyard

= 0.16

(iv) Railway Platform

= 0.24

(v) Foot- path

= 0.40

2.5) EVALUATION OF Grouted Macadam VIS-VIS DESIGNED BITUMINOUS MATERIAL.

Bituminous mixes used as surface courses of flexible pavement are visco-elastic materials and their properties are dependent upon stress, strain and temperatures. The induced strain in a bituminous material is attributable to viscous flow and increases with loading time and temperature. The other vital issue associated with failure of bituminous surfacing is loss of adhesion between binder and aggregate under the influence of water and also due to spillage of petroleum fuel from vehicles. The bituminous mixes have to fulfill a wide range of requirements to sustain traffic and environmental stresses. These are the resistance to permanent deformation and fatigue cracking, impermeable to protect lower layers of road from water, durable to resist abrasion of traffic and effects of temperature., water and oil spillage and contribute to pavement strength. It is important to study effect of water, temperature and oil on a material while comparing a new material like Grouted Macadam for its performance vis-vis bituminous material. The properties of Grouted Macadam vis-vis Bituminous concrete (BC) using 60/70 grade bitumen used for aggregate coating are given in Table 5

Table 5

Properties of Grouted Macadam vis-a-vis Bituminous Concrete using 60 / 70 grade bitumen

Properties

Values of BC using

Bitumen 60 / 70

Grouted Macadam

Limits

MORT & IRC specification

Bulk density, gm/cc

2.34

2.32-2.35

Marshall Stability , at 600C, kg, (ASTM D 1559)

940

2270

820 (min)

Marshall flow at 600C, mm, (ASTM D 1559)

3.2

4.2

2.0 - 4.0

Percent Air voids

4.2

3.0 - 6.0

Indirect tensile strength at 250C , kg /cm2

5.7

13.8

ASTM D 4123

Stiffness Modulus at different temperatures, kg/cm2 Poissons Ratio (m) = 0.35for bituminous materials and 0.25 for Grouted Macadam (ASTM D 4123)

150C

50920

184620

IRC - 37 - 2001 indicated value of elastic modulus of BC mix as 31260 kg / cm2 for 60/70 and 19660 kg/cm2 for 80/100 bitumen at 25oC

250C

24990

100390

350C

10640

79650

450C

1920

54530

Reduction in stiffness modulus values , %, (150C - 450C )

96

71

Not specified

Retained stability at 600C immersion in water at 600C for 24 hours , % , ( ASTM D 1075)

80

93

75 (min)

Retained indirect tensile strength at 250C immersion in water at 600C for 24 hours , %, (ASTM D 4867)

85

95

80 ( min )


Loss of material in diesel oil , 7 days immersion , %

4.2

0.3

Not specified


3) PAVEMENT DESIGN CALCULATION

Having quantified the important mechanical properties of Grouted Macadam in the laboratory an analytical design approach is used to develop guidelines for the use of Grouted Macadam in certain situation. Analysis of the pavement structure performed using layered linear elastic model and design calculation are involved using a conventional bituminous asphalt wearing course material and Grouted Macadam as an alternative surface layer material.

3.1) High performance pavement concrete in the design of flexible pavements (Bituminous Roads)

The Indian Road Congress vide IRC:37-2001 lays down the following guidelines for design of flexible pavements

3.1.1) Critical locations, Relationship between number of cumulative standard axles strain values and elastic modulus of materials.

Critical locations in pavement


A and B are the critical locations for tensile strains (e1). Maximum value of the strain is adopted for design. C is the critical location for the vertical subgrade strain (e2) since the maximum value of the e2 occurs mostly at C.

Fatigue criteria

Bituminous surfacing of pavements display flexural fatigue cracking if the tensile strain at the bottom of the bituminous layer is beyond certain limit. Based on the performance data of pavements of south, north, east and west zones in India collected under the research schemes of Ministry of Surface Transport Govt .of India, the relation between the fatigue life of the pavement and the tensile strain in the bottom of the bituminous layer was obtained as

NF =221*10-4(1/e1) 3.89 (1/E) 0.854

NF =Number of cumulative standard axles to produce 20% cracked surface area.

e1=Tensile strain at the bottom of BC layer (micro strain)

E =Elastic modulus of bituminous surfacing(Mpa)

The values of the elastic moduli of Bituminous concrete/Dense Bituminous Macadam and Bituminous Macadam meeting the specifications of the MOST are given below.

ELASTIC MODULUS (Mpa) VALUES OF BITUMINOUS MATERIALS

Mix Type

Elastic Modulus(at 35 0 C)

BC and DBM80/100 bitumen

975

BC and DBM 60/70 bitumen

1695

BC and DBM 30/40 bitumen (75 blow compaction and 4% air void)

2944

BM 80/100 bitumen

500

BM 60/70 bitumen

700

The poisson's ratio of bituminous layer may be taken as 0.50

Rutting Criteria

As large number of data for rutting failure of pavements were obtained from the research scheme of the Ministry of Road Transport and Highways and other research investigations setting and allowable rut depth as 20mm the rutting equation was obtained as

NR =4.1656*10-8{1/e2} 4.5337

NR =Number of cumulative standard axles to produce rutting of 20 mm

e2= Vertical subgrade strain (micro strain)

Modulus of Elasticity of subgrade, sub-base and Base layers

Subgrade

E(Mpa)= 10*CBR for CBR £5 and

= 176*(CBR) 0.64 for CBR ³5

Granular sub-base and Base

E2=E3*0.2*h 0.45

E2=Composite elastic modulus of granular sub base and base (Mpa)

E3=Elastic modulus of subgrade (Mpa)

h= Thickness of granular layers (mm)

Poisson's ratio for both the granular layer as well as subgrade layer may be taken as 0.4

Substitution of Dense Bituminous Macadam (DBM)

Part of the DBM can be substituted for BM on the basis of equal flexural stiffness given as

E1H13/12(1-m12)= E2H23/12(1- m12)

Where

E1 H1 m1 and E2 H2 m2 are the parameters (Elastic modulus, Thickness and Poisson's ratio) of the DBM and BM respectively. Based on the above equation following equivalent thickness may be used

Example

180mmDBM=125MMDBM+75mm BM

240 mm DBM=185mmDBM+75mm BM

240 mm of BM=75*(700/1695)1/3 = 55.85 mm of DBM

The equation of substitution of two different materials of Elastic modulus E1 and E2 assuming similar poisson's ratios for the two is

E1H13=E2H23

Which reduces to H2=(E1/E2)1/3*H1

This implies that if a material with 8 times the elasticity of bituminous material is used then the thickness of the pavement layer for same design life could be halved. Similarly if the material has 30 times the elasticity the thickness could be one third and so on

This paper reports the development of such a material whose total cost inclusive of mixing and placing is competitive to the cost of laying bituminous macadam. Presently this technology is being used in several states of India including Maharashtra, Goa, Gujrath and Jharkhand .for wearing course, strengthening of existing road and building new road. Organizations like MSRDC, MIDC,MMRDA, CIDCO,BMC are regularly using Grouted Macadam.

The trial stretches of road have been in regular use for high density commercial vehicle traffic for several years and the benefits are quantifiable. The high performance ,low life cycle cost concrete pavement technology has the potential to contribute significantly to development of the infrastructure in our country.

The pavement with Grouted Macadam it's cost and life is compared with existing methods of pavement making. The details are given in figure below.


4) Few illustative pictures of Indian road before and after overlaying with Grouted Macadam


A bridge deck of Mumbai-Pune Expressway after overlaying with Grouted Macadam


Typical road with potholes


Sion Circle -Mumbai after laying with Grouted Macadam

5) Discussion

The results show that using Grouted Macadam as a surfacing material can result in a saving in bituminous roadbase material .The reason is the higher stiffness modulus of Grouted Macadam compared to conventional hot rolled asphalt wearing course material. This additional stiffness helps distribute the loading applied by traffic better and as a result the expected pavement life is increased. The Grouted Macadam also showed lower temperature susceptibility compared to hot rolled asphalt.

The resistance to permanent deformation of the Grouted Macadam is high compared to a conventional hot rolled asphalt wearing course material. Consequently ,the Grouted Macadam can be used in highly stressed locations where traditional bituminous materials could rut under traffic loading. However, not all pavement rutting is confined to the wearing course. If Grouted Macadam is placed over granular or bituminous material with low deformation resistance the pavement could rut ,leading to cracking of Grouted Macadam due to loss of support.

6) Conclusion

· The Grouted Macadam pavement surface property of skid resistance and surface texture depth measured at site indicate the average skid resistance is adequate and mean texture depth data indicates the surface texture is coarse.

· The abrasion resistant of Grouted Macadam pavement surface is comparable to concrete pavement with pneumatic tyred traffic.

· The Marshall stability of cores of Grouted Macadam is 2.5 times higher than the stability of bituminous mixes used for surfacing of flexible pavement.

· Higher values of stiffness modulus indicate improved resistance to deformation for Grouted Macadam as compared to designed bituminous mix.

· Stiffness modulus values at different temperature indicate better resistance to temperature variation in case of Grouted Macadam compared to bituminous mix.

· Retained stability after immersion in water is 93 % for Grouted Macadam as compared to 80% in case of bituminous mix shows better resistant to damage by water.

· The negligible loss of material from core specimen of Grouted Macadam in diesel oil indicate resistance of Grouted Macadam against damage due to spillage of petroleum products.

· Design calculations have been performed using Grouted Macadam as a wearing course material in a flexible pavement construction.

· Grouted Macadam displays a type of performance between that of concrete and conventional bituminous materials.

7) References

1. Road Research Road Note No.27"Instruction for using British Portable Skid Resistance Tester" Department of Scientific and Industrial Research, RRL HMSO London,Year 1960

2. NCHRP Report No.37"Tentative skid resistance requirements for main rural highways, HRB" Year 1967.

3. Method of Test of Abrasion resistance of concrete as per IS 9284-1979

4. ASTM D 4867

5. ASTM D 1075 and ASTM D3637

6. ASTM D 4123 and ASTM D 1559

7. Assessment of LTPP friction Data, US Department of transportation ,FHWA March 1999

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