important aspects in road construction

8/3/2019 Important Aspects in Road Construction

1/89


2/89


3/89

305. Soils unsuitable for embankment,sub grade and shoulders

(i) Material from swamps, marshes and bogs.(ii) Peat, log, stump and perishable material; soil

classified as OL, OI, OH or Pt as per IS:1498.(iii)Materials susceptible to spontaneous combustion.(iv)Clay having liquid limit exceeding 70% and

plasticity index exceeding 45%. (tests conductedon material passing 0.425 mm IS Sieve as perIS:2720 part 5)

(v) Material with salts resulting in leaching action e.g.Soils of pH > 8.5).(vi) Expansive clay with free swelling index (test

conducted on material passing 0.425 mm IS Sieve

as per IS:2720 part 40) exceeding 50%


4/89

305. Soils unsuitable for embankment,

sub grade and shoulders continued

(vii) Materials in a frozen condition.

(viii) Fill materials with a soluble sulphate contentexceeding 1.9 gm of sulphate, (expressed as SO3) per litrewhen tested in accordance with BS:1377 test 10, but using

-

or other distance described in the Contract, of concrete,cement bound materials or other cementitious materialsforming part of permanent works.

(ix) Material with a total sulphate content (expressedas SO3) exceeding 0.5 per cent by mass when tested inaccordance BS: 1377 test 9, shall not be deposited within500 mm or other distance described in the Contract, of

metallic items forming part of permanent works


5/89

305.4.4: Embankment and Sub Grade

Requirements around structures

The filling around culverts, bridges and other

structures upto a distance of twice the height ofthe road from the back of the abutment shall becarried out inde endent of the work on the main

embankment.Material with LL more than 40% and PI more than20% shall not be allowed as backfill for all earth

retaining structures. Backfill material shallconform to the general requirements given in

appendix 6 of IRC: 78 (Standard Specifications

and Code of practice for road bridges-section VII)


6/89


7/89

Soil group to

IS: 1498-1970 Visual

description

MDD

Kg/ m3OMC %

range

Anticipated

performance

Most

probablepossible

GW,GP,G

Granular 1850 to Good to

Filling behind abutments, retaining walls and retun wallsGeneral guide to the selection of soils on basis of anticipated

embankment performance appendix - 6, IRC: 78-2000

, ,HP

-

materials

2280-

Excellent

SB, SM,GM, GC,SM, SC

-

Granularmaterials

With soils

1760 to2160

9 - 18Fair to

excellent

SP - sand1760 to

185019 - 25

Fair togood

MI, MH,

DL

CL,

SM,SB,SC

Sandy soils &

silts

1760 to

2080 10 - 20

Fair to

good


8/89

Some Test Results on Soils done at Soil Testing Cell (R&B) Vijayawada

District classification

LL

%

PI

%

OMC

%

MDD

g/cc

FSI

%

CBR

%

Guntur CH 66 33 21.3 1.6 65 3

Krishna CI 48 24 19.2 1.63 46 3

Prakasam SM - NP 13.7 1.90 - 10

W G CI 39 21 26 1.45 65 4

Kurnool SC 24 12 8.29 1.75 - 9

W G CL 31 13 15.7 1.84 33 6

E G CI 48 24 14.3 1.82 33 7

Prakasam CH 61 32 24.5 1.4 95 3

W G CI 49 29 16.7 1.68 200 5


9/89

401.Granular Sub Base as Drainage Layer:

Permeability requirement for drainage layer is 20 m/dayas per Pavement Design Guide (1986) by AmericanAssociation of State Highway and Transportation Officials

(AASHTO) and 4/6 laning manual

Table: 300-4 of Orange Book: Grading Requirements for

A re ate Drains

IS Sieve size Percent passing by weight

37.5mm 100

9.5mm 45 - 100

3.35mm 25 - 80

600 micron 8 - 45

150 micron 5 - 10

75 micron < 5


10/89

401 Granular Sub Base

1) Material passing 75 micron sieve shall be less than10%2) Material in mix shall have 10% fines value (for sample insoaked condition as per with BS: 812 (part III) > 50 KN3) Water Absorption(IS: 2386-part 3) of coarse aggregate 2%.If

it is more, soundness test requirements be satisfied.4) Material in mix passing 425 micron sieve shall have

Liquid limit < 25% and Plasticity index < 6%.5) Material in the mix shall satisfy specified grading

6) CBR test (IS: 2720 part 16). In-situ CBR tests are not reliable.

30% CBR (4 day soaked) for design traffic more than 2 msaas per IRC:37-200120% CBR (4 day soaked) for design traffic less than 2 msaas per IRC:37-2001

7) Layer thickness:100 mm compacted with smooth wheeled roller

225 mm compacted with vibratory roller


11/89

TABLE 400-1, Grading for Close Graded Granular Sub-Base

(for gravel roads as per Rural Roads Manual IRC:SP 20-2002)

IS SieveDesignation

Grading I Grading II Grading III

75.0 mm 100 -- --

53.0 mm 80-100 100

26.5 mm 55-90 70-100 1009.50 mm 35-65 50-80 65-95

4.75 mm 25-55 40-65 50-80

2.36 mm 20-40 30-50 40-65

0.425 mm 10-25 15-25 20-35

0.075 mm 3-10 3-10 3-10


12/89

TABLE 400-2. GRADING FOR COARSE GRADEDGRANGULAR SUB-BASE MATERIALS

IS SieveDesignation

Percent by weight passing throughthe IS sieve

Grading I Grading II Grading III

75.0 mm 100 -- --

53.0 mm 100

26.5 mm 55-75 50-80 100

9.50 mm

4.75 mm 10-30 15-35 25-45

0.075 mm < 10 < 10 < 10

CBR Value(Minimum)

30 25 20


13/89

Coarse Aggregates: Gr-I to Gr-III , 40mm & 65 mm

Screenings: Type-A :6mm and 10mm,Type-B: Stone Dust

Binder: Stone Dust

Process of WBMSpreading Metal > Sectioning and Dry Rolling >

Light Sprinkling of Water > rolling > Application ofScreenings > Brooming > Rolling > Watering &

Sweeping > Rolling > Application of Binder >Sprinkling of Water & Sweeping > Rolling > Settingand Drying


14/89

Table 400-7, WBM gradation Requirements

IS Sieve

size

Cumulative percent passing

Grade I Grade II Grade III

125mm 100 - -90mm 90-100 100 -

63mm 25-60 90-100 100

53mm - 25-75 95-100

45mm 0-15 0-15 65-90

22.4mm 0-5 0-5 0-1011.2mm - - 0-5

Aggregate Impact Value (IS:2386: part-4) :30% (max)

Combined flakiness and elongation index (IS:2386: part-1) : 30% (max),


15/89

Table 400 - 8

404.2.6. Screenings: Screenings to fill voids in thecoarse aggregate shall generally consist of the same material

as the coarse aggregate. However, where permitted,predominantly non-plastic material such as moorum or gravel(other than rounded river borne material) may be used for thispurpose provided liquid limit and plasticity index of suchmaterial are below 20 and 6 respectively and fraction passing75 micron sieve does not exceed 10 per cent.

Type of screenings IS Sieve % passing

Type A 13.2mm

(6mm & 10mm chips)

13.2mm 100

11.2mm 95-100

5.6mm 15-35180 micron 0-5

Type B 11.2mm

(stone dust)

11.2mm 100

5.6mm 90-100

180 micron 15-35


16/89

DOs Donts

1. Check aggregates for

Soundness test when waterabsorption is more than 2%

2. Soft aggregate should be

tested for wet aggregate impactvalue.3. Construct shoulders

simultaneously along with

1. Do not use any material derived from

rocks e.g. phyllites, shales or slates.2. Do not use local soil and clayey

material as screenings or binding

material unless it meats the

requirements of PI mentioned

3. Do not use binding material if

screenings are of crushable type.

4. Do not spread coarse aggregate more

than 3 days in advance of any

WBM layers.4. Use inverted choke over fine

grained soil sub-grade.5. Remove BT surface before

WBM is laid on an existingblack top road.

6. Remove defective macadam tofull depth and replace by freshmaterial and re-compact.

subsequent operations.

5. Do not roll if sub-grade is soft or

yielding or causes a wave like motion

while rolling.

6. Do not lay WBM layer on lime treated

sub-base until it has attained its strength.7. Do not use screenings to make up

depressions.

8. Do not allow traffic till WBM is fully

set.


17/89

DOs Donts

1. Check aggregates for

Soundness test when waterabsorption is more than 2%

2. Soft aggregate should be

tested for wet aggregate impactvalue.3. Construct shoulders

simultaneously along with

1. Do not use any material derived

from rocks e.g. phyllites, shales orslates.2. Do not use local soil and clayey

material as screenings or bindingmaterial unless it meats the

requirements of PI mentioned3. Do not use binding material ifscreenings are of crushable type.

4. Do not spread coarse aggregate

WBM layers.4. Use inverted choke over fine

grained soil sub-grade.5. Remove BT surface before

WBM is laid on an existingblack top road.

6. Remove defective macadam tofull depth and replace by freshmaterial and re-compact.

subsequent operations.5. Do not roll if sub-grade is soft oryielding or causes a wave likemotion while rolling.

6. Do not lay WBM layer on lime

treated sub-base until it has attainedits strength.7. Do not use screenings to make updepressions.8. Do not allow traffic till WBM is

fully set.


18/89

WET MIX MACADAM

IS Sieve DesignationPer cent by weight

passing the IS Sieve

53.00 mm 100

45.00 mm 95-100

22.4 mm 60-80

11.20 mm 40-60

Table 400-11. Grading Requirements of Aggregates for WMM

Materials : 40mm, 20mm , 12mm, 6mm &Stone Dust Mixing at Pug Mill with Water,Conveyed to Site, Spreading by Paver and Rolling. Relative Compaction = 98 %

Aggregate Impact Value (IS:2386: part-4) :30% (max)

Combined flakiness and elongation index (IS:2386: part-1) : 30% (max),Plasticity Index (IS:2720: part5) shall not exceed 6%.

4.75 mm 25-402.36 mm 15-30

600.00 micron 8-22

75.00 micron 0-8


19/89

DOs Donts

1. Ensure compliance of allmaterial and plantrequirements.

2. Check aggregate forsoundness test whenwater absorption is more

1. Do not use materialother than crushedstone.

2. Do not allowsegregation or pockets of

an .3. Build shoulderssimultaneously along withWMM layers.

4. Remove BT surfacebefore WMM is laid on anexisting road.

coarse ne ma er a onthe layer.

3. Do not allow any trafficon the WMM surfacewithout covering it with awearing course.


20/89

Bitumen

grade

Penetration at

25C

Viscosity at 60C in

Poises

Kinematic

viscosity at 135C,

cSt, Min

VG - 40 40 to 6040 to 60 4000200 400

Important Requirements Viscosity

Grades of Bitumen as per IS: 73 - 2006

VG - 30 50 to 7050 to 70 3000600 350

VG - 20 60 to 8060 to 80 2000400 300

VG - 10 80 to 10080 to 100 1000200 250


21/89

Stipulations of IS: 73 2006 in selection of VG grade bitumensin place of Penetration Grade (prevailing) bitumens

Viscosity Grade General Applications

VG-40

(40 to 60 penetration)

Use in highly stressed areas suchas those in intersections, near tollbooths and truck parking lots in

lieu of old 30/40 penetration grade

Use for paving for most parts of


India in lieu of old 60/70penetration grade.

VG-20


Use in cold climatic, high altituderegions of North India

VG-10 (80 to 100penetration)

Use in spraying applications suchas surface dressing and paving invery cold climatic region in lieu of

old 80/100 penetration grade


22/89

BitumenBitumenTemp.C

AggregateTemp.C

MixTemp.C

LayingTemp. C

RollingTemp.C

VG - 40 160 - 170 160 - 170 160 170 150 min. 100 min.

Mixing, laying and rolling temperatures for VG grade

paving bitumen and modified binder

- - . .

VG - 20 145 165 145 165 145 165 135 min. 85 min.

VG - 10 140 160 140 160 140 160 130 min. 80 min.

Modified 165 - 185 155 175160

maximum130

Minimum115

minimum


23/89

Manufacturing and Rolling Temperatures

for penetration grade bitumen

Bitumen

Penetration

Bitumen

Mixing -C

Aggregate

Mixing-C

Mixed

Material -

C

MinimumRolling

temp.

C

Laying-C

35- -

(30-40)

65

(60-70)

150 - 165 150-170 165 Max 90 Min 125 Min

90

(80-100)

140 - 160 140-165 155 Max 80 Min 115 Min


24/89

Factors Influencing Compaction of Asphalt mixes

1) Type of Aggregates2) Shape of Aggregates

3) Grading of mix4) Residual moisture content in aggregates5) Binder conent

6) Viscosity of binder7) Temperature of mix during compaction

Note: The first six requirements are taken care inthe mix design, leaving temperature ofcompaction as the single most important affectingthe final result.


25/89

Recommended use of Cationic Emulsions

as per IS 8887: 2004

Type Recommended uses

Rapid Setting RS 1 Tack Coat

Rapid Setting RS 2 Surface Dressing

Medium Setting MS Pre mixes and plant mixes

Slow Setting SS 1Fog seal, Crack Seal, Prime

Coat

Slow Setting SS 2 Slurry Seal and mixes withhigher fine aggregate %

Slow Setting SS 1 is being used as tack coat in USA

and other countries


26/89

Designation

Grade and RequirementsMethod of

testCRMB60

CRMB55

CRMB50

Table 500-46, Specifications for modified bitumen

Penetration at 25C 50 - 70 50 - 60 40- 60

-

1978

Softening point C-min

50 55 60IS: 1205-

1978

Elastic recovery at15C-minimum

40 35 30ASTM D5976

1996


27/89

Minimumpavement

temperature

in C

Maximum Atmospheric Temperatures in C

< 35o

c 35o

c to 45o

c > 45o

c

< - 10 ocPMB/NRMB - 120

CRMB - 50

PMB/NRMB - 70

CRMB - 55

PMB/NRMB - 70

CRMB - 55

Selection Criteria for type of modified bitumen basedon Atmospheric temperature

+10 oc to-10 oc

PMB/NRMB - 70CRMB - 50



> 10 ocPMB/NRMB - 70

CRMB - 55

PMB/NRMB - 70

CRMB - 55

PMB/NRMB - 40

CRMB - 60

PMB - Polymer Modified BitumenNRMB- Natural Rubber Modified Bitumen

CRMB- Crumb Rubber Modified Bitumen


28/89

Prime Coat over granular base

Application of single coat of low viscosity liquid bituminousmaterial to an absorbent granular surface for anysuperimposed bituminous treatment

Table 500-1,Viscosity requirements and quantity of bituminous primer

Prime Coat over granular base

Application of single coat of low viscosity liquid bituminousmaterial to an absorbent granular surface for anysuperimposed bituminous treatment

Table 500-1,Viscosity requirements and quantity of bituminous primer

KinematicViscosity of Quantity / 10r mer at o (Centistokes)

q.m gs

low porosity 30 60 6 to 9

Mediumporosity

70 140 9 to 12

High porosity 250-500 12 to 15


29/89

Methodology for Prime Coat

1. Bituminous primer should be slow setting bitumenemulsion, use of cutback being restricted to areas having subzero temperature or for emergency operations.

2. The prime coat should be applied only on the top

most granular base layer, over which bituminous treatment isto be applied. The granular base surface should be sweptclean of dust and loose particles and where required, lightly

and uniformly sprinkled with water to moist the surface.3. The primer should be sprayed uniformly over the drysurface of absorbent granular base, using suitable bitumenpressure distributor or sprayer capable of spraying primer at

specified rates and temperature so as to provide a uniformlyunbroken spread of primer. Normal temperature range ofspraying emulsion should be 20C to 60 C. The rate of application depends upon the porosity characteristics of the

surface to be primed and is given in above table.


30/89

DOs Donts

1. Use slow setting emulsionand restrict the use ofcutback to subzero

temperature conditions oremergency operations.2. Use only pressure

1. Do not apply primerwhen the atmospherictemperature in shade is

less than 10C or whenthe weather is foggy, rainy

or windy.sprayers.

3. Preferably lay a trialsection.

4. The Contractor to

demonstrate at a sprayingtrial to ensure that theequipment is capable of

producing a uniform spray.

. o no a ow pour ng oprimer using perforatedcans.3. Do not allow traffic on

primed surface.4. Do not applybituminous material to a

wet surface.


31/89

Table 500-2, rate of application of tack coat

Bituminous material

503 Tack Coat ( MORT & H )503.4.3: The application of tack coat shall be at the rate

specified in the contract and shall be applied uniformly. Ifrate of application of tack coat is not specified in the

contract then it shall be at the rate specified in table 500-2

Kg/10 Sq.MNormal bituminous surfaces 2.0 to 2.5

Dry and hungry bituminous surfaces 2.5 to 3.0

Granular surfaces treated with primer 2.5 to 3.0Non- bituminous surfaces:

Granular base (not primed)

Cement concrete pavement

3.5 to 4.0

3.0 to 3.5


32/89

S.No Type ofsurface

Rate of

spray(emulsion)

K /M2

Rate of spray

(Bitumen -VG-10)K /M2

Rate of application of tack coat

as per table 4 of IRC:SP: 78-2008

iBituminous

surface0.20

to 0.300.30 to 0.40

ii

Granularsurface

treated withprimer

0.25to 0.30

0.35 to 0.40


33/89

Methodology for Tack Coat

1. Use a rapid setting bitumen emulsion for applying a tack coat,the use of cutback being restricted to areas having sub-zerotemperature or for emergency applications.2. The surface on which tack coat is to be applied should be

clean, free from dust, dirt and any extraneous materials and dry.3. The surface should be prepared as per sub-section 501.4. The binder should be sprayed uniformly over the surfaceusin suitable bitumen ressure s ra er ca able of s ra in

bitumen and emulsion at specified rates and temperature so asto provide a uniformly unbroken spread of bitumen emulsion.For smaller jobs, a pressure hand sprayer may be used. Normalrange of spraying temperature should be 20C-60C in case of

emulsion and 50 C-80C in case of cutback. The rate of application depends upon the type of surface and is given inabove Table.5. The surface should be allowed to cure until all the volatiles

have evaporated.

DO D t


34/89

DOs Donts

1.Plan the work so that nomore than the necessarytack coat for the daysoperation is placed on

surface.

1. Do not apply tackcoat whenatmospherictemperature is less

than 10C or whenweather is foggy, rainy

cutback carefully to avoidfire mishap.

2. Do not apply tackcoat on a wet surface.

3. Do not allow anyequipment or vehicles

on Tack Coat.


35/89

Physical Requirements of Coarse Aggregates forBM/DBM/SDBC/BC

Table 500-3 for BM, table 500-8 for DBM, table 500-14 forSDBC & 500-17 for BC of 4th Revision

Property Test Specification

Code

Reference

CleanlinessGrain sizeanalysis

Max. 5% passing0.075mm sieve

IS: 2386 part1

Particleshape

Flakiness andElongation

IndexMax. 30% IS: 2386 part

1

Strength

Los Angeles

Abrasion Valueor

Max. 40% for BM ,

35% for DBM & SDBC&30% for BC

IS: 2386 part4

Aggregate

Impact Value

Max 30%for BM,27%for DBM & SDBC,

24%for BC

IS: 2386 part

4

h i l i i d


36/89

DurabilitySoundness:

Sodium Sulphate

Magnesium Sulphate

12%

18%

IS: 2386 part 5

Absorption Water Absorption 2% IS: 2386 part 3

Coating and Stripping

Physical requirements continued

o ggregate tumen :

WaterSensitivity

Retained TensileStrength Min. 80%

to be done ifstripping fails

Polishing Polished Stone Valuefor SDBC and BC

Min. 55 Bs: 812 part114


37/89

513 Seal Coat

Requirement of materials fo seal coat

Type

Aggregate Bitumen Emulsion

SpecificationSize mm

Quantitycum

specification QuantityKg/10 sqm

specification QuantityKg/10sqm

-

A

. .

6mm 0.09 S-65 9.8 RS 15.0

B

2.36- 0.18

Sand ordust

0.06 S-90 6.8 SS 10.0

Type A seal coat is for high rainfall areas ( over 1500mm )

Table 500 4 COMPOSITION OF BITUMINOUS MACADAM (4th Revision)


38/89

Table 500-4, COMPOSITION OF BITUMINOUS MACADAM (4th Revision)

Mix Designation Grading I Grading II

Nominal AggregateSize

40 mm 19 mm

Layer Thickness 80 100 mm 50 75 mm

IS Sieve (mm) Cumulative % by weight of total aggregate passing

45 100 -----

37.5 90 100 ------

26.5 75 100 100

19 --- 90 10013.2 35 61 56 88

4.75 13 22 16 36

2.36 4 19 4 19

0.30 2 -10 2 -10

0.075 0 -8 0 -8

Bitumen content, % 3.10 3.40 3.30 3.50

Bitumen Grade 35 to 90 35 to 90

Cl 4 2 3 1 of IRC: 37 2001


39/89

Cl. 4.2.3.1 of IRC: 37-2001BM has low binder content and high

voids and is thus not impervious to water.Effect of high voids is reduced stiffness and

increased stress concentrations. From fatigueconsiderations, the detrimental effects ofvoids is more a arent at low tem eratures.

During prolonged hot spells, BM mix willoperate over a very low stiffness range.

Hence, use of BM may desirably be

restricted only to roads designed to carrytraffic less than 5 msa. DBM is recommendedfor roads designed to carry higher traffic than

5 msa

Methodology for Bituminous Macadam


40/89

Methodology for Bituminous Macadam1. Prepare the base on which bituminous macadam

course is to be laid and shape to the specified lines, grade andcross-section.

2. Apply tack coat over the base preparatory to laying ofthe bituminous macadam.

3. Bituminous Macadam should be prepared in a Hot MixPlant of adequate capacity Ensure manufacturing and rollingtemperatures for Bituminous Macadam as specified.

.

lay by means of an approved self-propelled mechanical paver.5. Commence initial rolling with 80-100 kN rollers (three-

wheel or tandem type), beginning from the edge and progressing towards the centre longitudinally. On super

elevated portions, rolling should progress from lower to upperedge parallel to centre line of pavement. Thereafter, do intermediate rolling with vibratory or pneumatic tyred roadrollers. This should be followed by final rolling while the

material is still workable.

Methodology for Bituminous Macadam continued


41/89

Methodology for Bituminous Macadam continued6. Any high spots or depressions noticed after the roller has

passed over the whole area once should be corrected byremoving or adding premixed material. Rolling shouldrecommence thereafter. Each pass should have an overlap of atleast one-third of the track made in the preceding pass.

Rolling should be continued till all roller marks have beeneliminated.7. For single lane roads no longitudinal joint is required, while

-

depending on the paver width.8. For making longitudinal or transverse joint, cut the edges ofthe bituminous layer laid earlier to their full depth so as toexpose fresh surface and apply a thin coat of binder. Lay

adjacent new layer and compact flush with the existing layer. 9.Cover the bituminous macadam with the wearing course withina period of 48 hours. If there is any delay in providing wearingcourse the bituminous macadam surface should be covered

with a seal coat before opening to traffic.

DOs Donts


42/89

1.Ensure that stone aggregate

conforms to the physicalrequirements and gradingrequirements and are dry and clean.2. In case the aggregate has pooraffinity to bitumen use anti strippingagent with the approval of Engineer.3. While transporting the mixture itshould be suitably covered by

1. Do not undertake the work infoggy, rainy or windy weather orwhen the atmospheric temperaturein the shade is less than 10C.2. Do not allow the difference intemperature of binder and

aggregate to increase beyond 14OCat any time.3. Do not allow the premix materialto adhere to the roller wheels. (Do

arpau n.

4. Rolling operations should becompleted before the mix becomesunworkable5. Maintain strict control on

temperature while mixing androlling.6. Regulate the rate of delivery ofmaterial to paver to enable it to

operate continuously.

no use excess wa er or e

purpose. Light sprinkling shoulddo.)4. Do not use lubricating oil on thewheels of the roller to prevent mixfrom adhering.

5. Do not allow traffic until the mixhas been covered with a wearingcourse.6. Do not move roller at a speed

more than 5 km/h.


43/89

Mix Design of DBM, SDBC or BC

1 Proportioning of Coarse aggregate and Fine

aggregate to satisfy the specified gradation.

specified values of:a) Marshal Stability Valueb) Flow Value

c) Voids in Mineral Aggregate (VMA)d) Voids Filled by Bitumen (VFB)e) Air Voids in Mix

Table 500-10 Composition of Dense Graded Bituminous Macadam Pavement Layers.


44/89

p y

Grading 1 2

Nominal aggregate size 40 mm 25 mm

Layer Thickness 80-100mm 50-75 mm


45 100

37.5 95-100 100

26.5 63-93 90-100

- -

13.2 55-75 56-804.75 38-54 38-54

2.36 28-42 28-42

0.3 7-21 7-21

0.075 2-8 2-8

Bitumen content % bymass of total mix

Min 4.0 in 4.5

Bitumen grade (pen) 65 or 90 65 or 90


45/89

Description Requirements

Minimum stability (KN at600C)

9.0

Minimum flow (mm) 2

Maximum flow (mm) 4

Table 500-11, Requirements of DBM layer

Compaction level (Number ofblows)

75 blows on each face ofthe specimen

Percent air voids 3-6

Percent voids in mineral

aggregate (VMA) See table 500-12

Percent voids filled withbitumen (VFB)

65-75


46/89

IS Sieve(mm)

Cumulative per cent passingby weight of total aggregate

0.6 100

0.3 95 - 100

-

Table 500-9, Grading Requirements of mineral filler

.

The filler shall be free from organic impurities and have a Plasticity

Index not greater than 4. The Plasticity Index requirement shall not apply iffiller is cement or lime. When the coarse aggregate is gravel, 2 per centbyweight of total aggregate, shall be Portland cement or hydrated lime and the

percentage of fine aggregate reduced accordingly. Cement or hydrated limeis not required when the limestone aggregate is used. Where the aggregates

fail to meet the requirements of the water sensitivity test in Table 500-8, then2 per cent by total weight of aggregate, of hydrated lime shall be addedwithout additional cost.

Table 500-12, Minimum per cent voids in mineral aggregate (VMA)


47/89

NominalMaximum

particle size

Minimum VMA, per cent related to design airvoids, per cent

3.0 4.0 5.0

9.5 14.0 15.0 16.0

12.5 13.0 14.0 15.0

, p gg g ( )

19.0 12.0 13.0 14.0

25.0 11.0 12.0 13.0

37.5 10.0 11.0 12.0

Notes: 1. The nominal maximum particle size isone size larger thanthe first sieve to retain more than 10%.

2. Interpolate minimum voids in the mineral (VMA) for design air voids

values between those listed

Table 500-15 Composition Of Semi Dense Bituminous Concrete Pavement Layers.


48/89

Grading 1 2



IS Sieve (mm) Cumulative %by weight of total aggregate passing

19 100

13.2 90-100 100

9.5 70-90 90-100

. - -

2.36 24-39 24-39

1.18 15-30 15-30

0.3 9-19 9-19

0.075 3-8 3-8Bitumen content % by

mass of total mixMin 4.5 Min 5.0

Bitumen grade (pen) 65* 65*

* Only in exceptional circumstances, 80/100 penetration grade bitumen may be used


49/89

Description Requirements

Minimum stability (KN at600C)

8.2

Minimum flow (mm) 2

Maximum flow (mm) 4

Table 500-16, Requirements of SDBC layer

Compaction level (Number ofblows)

75 blows on each face ofthe specimen


Percent voids in mineral

aggregate (VMA) See table 500-12

Percent voids filled withbitumen (VFB)

65-78

Table 500-18 Composition of Bituminous Concrete Pavement Layers.


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Grading 1 2




26.5 100

19 79-100 100

13.2 59-79 79-100

9.5 52-72 70-88

4.75 35-55 53-712.36 28-44 42-58

1.18 20-34 34-48

0.6 15-27 26-38

0.3 10-20 18-28

0.15 5-13 12-20

0.075 2-8 4-10

Bitumen content % bymass of total mix

5.0 - 6.0 5.0 - 7.0

Bitumen grade (pen) 65 65

Table 500-19, Requirements of BC layers


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Minimum stability (kN at60 C)

9.0

Minimum flow (mm) 2

Maximum flow (mm) 4Compaction level(Number of blows)

75 blows on each of the twofaces of the specimen

q y


Percent voids in mineralaggregate (VMA)

See table 500-12

Percent voids filled with

bitumen (VFB) 65-75

Loss of stability onimmersion in water at

60C (ASTM D 1075

Minimum 75 % retainedstrength

Table 5500-13, Permissible variations from job mix formula for DBM, SDBC, and BC


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Description Permissible variation

Base/binder course Wearing course

Aggregate passing 19mm sieve or

larger

8% 7%

Aggregate passing 13.2mm, 9.5mm 7% 6%

Aggregate passing 4.75mm 6% 5%

Aggregate passing 2.36mm, 1.18mm,0.6mm

5% 4%

Aggregate passing 0.3mm, 0.15mm 4% 3%

Aggregate passing 0.075mm 2% 1.5mm

Binder content 0.3% 0.3%

Mixing temperature 10C 10C

Reasons for Poor performance of Asphalt mixes


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Reasons for Poor performance of Asphalt mixes

1 Inadequate initial compaction making themix vulnerable to high secondary compaction

under traffic.2 Relatively high asphalt contents thatpermit the reduction of air voids to less than 3per cent under secondary compaction, leadingto rutting under heavy axle loads whenpavement temperatures rise in summer.

3 Low asphalt contents and high air voids

in the mix leading to top- down cracking,raveling and stripping making the mix lesdurable.


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Modified Penetration Macadam (MPM) 506 Rural Roads Manual


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Description

Rate of application for 10sqm area

75mm 50mm

Bituminoussurface,

cum

On WBMsurface,

cum

Bituminoussurface,

cum

On WBMsurface,

cum

40mm size handbroken metal

0.9 0.6

12mm size chi s 0.18 0.18

Description

Bitumen rate of application for 10sqm area (kg)

75mm 50mm

Bituminoussurface On WBMsurface Bituminoussurface On WBMsurface

Bitumen for grouting

Tack coat for existing

bituminous surface

20

5

20

-

17.5

5

17.5

-

1. Spread coarse aggregate of 40 mm size metal uniformly at the rate of 0.9cum for 75 mm thickness (0.6 cum for 50 mm thickness) per 10 sqm area to


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( ) p qproper camber/ super-elevation. Remedy all high spots and depressions by

removing or adding aggregates.2. Commence rolling with 80-100 kN rollers (three-wheel or tandem type),beginning from the edge and progressing towards the centre longitudinally. Onsuper elevated portions, rolling should progress from lower to upper edge

parallel to centre line of pavement.3. Correct any irregularities noticed after the roller has passed over the wholearea once by loosening the surface and removing or adding the coarseaggregates followed by rolling. Continue rolling till the entire surface has beenrolled to desired compaction such that there is no crushing of aggregates and al

roller marks have been eliminated. Each pass of roller should overlap not lessthan one-third of the track made in the preceding pass.4. Heat bitumen (paving grade S-35 to S-90) to a temperature of 160C to180C and spray uniformly on aggregate layer at the rate of 20 kg per 10 m2 for

75 mm thick layer and 17.5 kg per 10 m2

for 50 mm thick layer.5. Immediately after application of bitumen, spread 12 mm size key aggregatesat a uniform rate of 0.18 cum for 75 mm thickness (0.12 cum for 50 mmthickness) per 10 m2 so as to cover the surface completely and roll. Rollingshould continue until the key aggregates are firmly embedded in position and

stop moving under roller

DOs Donts


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1. Ensure that aggregatesconform to gradingspecified and are dryand clean at the time of

laying.

1. Do not undertake thework in foggy. rainy orwindy weather or whenthe atmospheric

temperature in theshade is less than l0C.

.

temperature of bitumenappropriate tothe grade of bitumen.

3. Remove excessivedeposits of binder

during spray operation.

2. Do not allow anytraffic over Built upspray grout

without laying wearingcourse or seal coat.

512 Open Graded Pre Mix Carpet (OGPC)20 mm thick pre mix carpet


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20 mm thick pre mix carpet

Aggregate013.2mmchips = 0.18cum11.2mm chips = 0.09cum

(13.2mm = passing 22.4 & retained on 11.2mm sieves11.2mm chips passing 13.2mm

AIV < 40%, FIV < 25% and WA < 1% for coarse aggregates.

reta ne on 5.6mm s eves

BinderBitumen @ 14.6 kg/ 10sqmEmulsion @ 21.5 kg/ 10sqm

Appropriate technology and machinery for


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pp p gy y

Premix Carpet

1.Applying Prime Coat : Hand-held lance providedwith sprayer, operated by compressor

2.Applying Tack Coat : Hand-held lance provided,

3.Mixing of aggregates and bitumen in : Mini HotMix Plant, capacity of with specified quantities

around 6 tonnes/hour

4.Transporting from the mixer to site : Tarpaulin-

covered tractor-trailer or hand barrows

Methodology for OGPC1 Mixing should be thorough to ensure that a homogenous mixture is


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1.Mixing should be thorough to ensure that a homogenous mixture is

obtained. The temperature of bitumen at the time of mixing should be in therange of 150 C to 163 C and that of aggregates 155C to 163C, providedthat the difference between the temperature of aggregate and the binder shouldnot exceed 14C. If modified bitumen is used, temperature should be asrecommended in Subsection 512. The temperature at the time of discharge of

the mixture should be between l30C and 160C.2. The premixed material shall be spread on the road surface with rakes.3. Commence rolling with 80-100 kN rollers (three-wheel or tandem type),

.

super elevated portions, rolling should progress from lower to upper edgeparallel to centre line of pavement). Continue rolling operations till a smoothuniform surface is achieved and all roller marks are eliminated. Each passshould have an overlap of at least one-third of the track made in the precedingpass.

4. Correct any high spots or depressions noticed after the roller haspassed over the whole area once by removing or adding premixed material andre-compacting.

5. Provide a seal coat to the surface immediately after laying the carpet

as per details in Sub-section

DOs Donts

1 Ensure that the 1 Do not allow manual


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1. Ensure that the

aggregates and bindersatisfy the specifiedrequirements.

2. Before opening thebitumen emulsion drum,

1. Do not allow manual

mixing.

2. Do not undertake work

in foggy, rainy or windyweather or when theminimum air temperature

ro e rum a s ow

speed, to and fro at leastfive times for a distance ofabout 10 m to ensure

proper distribution ofstorage sedimentation.

3. As far as possible use

suitable cold mixin lant

s ess an .

3. Do not allow any trafficunless the emulsion is

properly set and thesurface has acquiredadequate stability


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512 Mix Seal surfacing


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Table 500-26, aggregate gradationIS sieve

designation

(mm)

Cumulative per cent by weight oftotal aggregate passing

Type A Type B

13.2 mm - 100

11.2 mm 100 88 - 100

5.6 mm 52 - 88 31 - 52

2.8 mm 14 - 38 5 - 25

0.090 mm 0 - 5 0 - 5

Bitumen 22 kg / 10 sqm 19 kg / 10 sqm

As per Manual for construction and supervision ofbituminous works Type A grading may be used for 25mm

thick MSS also, by proportionately increasing bitumen

content

Stone Matrix AsphaltA IRC SP 79 2008


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As per IRC: SP: 79 -2008

SMA is a gap graded hot mix which contains:a) Coarse aggregate: 70-80%

b) binder content: 6-7%c) filler: 8-12%

. .

e) layer thickness: 40 to 75mm

Bitumen for SMA shalll be VG-30 grade

bitumen or PMB-40 grade BitumenFiller shall be stone dust and /or hydrated lime

passing in 0.3mm sieve by 95 100% and in

0.075mm sieve by 85 100%


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Causes of superior performance of SMA

1) Higher amount of coarse aggregateprovides better stone-to-stone contact,which rovides hi hl rut resistant

bituminous course.2) Higher binder content adds durability3) Stabilising additive reduces drain

down of binder

Physical Requirements of Coarse Aggregates for SMAPhysical Requirements of Coarse Aggregates for SMA

CodeCode


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PropertyProperty TestTest SpecificationSpecificationCodeCode

ReferenceReference

CleanlinessCleanliness Grain size analysisGrain size analysis% passing 0.075mm sieve% passing 0.075mm sieve

< 2%< 2%IS: 2386 part 1IS: 2386 part 1

ParticleParticle

shapeshape

Combined FlakinessCombined Flakiness

and Elongation Indexand Elongation Index

< 30%< 30% IS: 2386 part 1IS: 2386 part 1

StrengthStrength

Los Angeles AbrasionLos Angeles Abrasion

ValueValue< 25%< 25%

IS: 2386 part 4IS: 2386 part 4

ggrega e mpac a ueggrega e mpac a ue 55%> 55%

durabilitydurability

Soundness (either Sodium or Magnesium)Soundness (either Sodium or Magnesium) 5 cycles5 cycles

Sodium SulphateSodium SulphateIS: 2386 part 5IS: 2386 part 5

< 12%< 12%

Magnesium SulphateMagnesium Sulphate < 18%< 18%WaterWater

AbsorptionAbsorptionWater AbsorptionWater Absorption IS: 2386 part 3IS: 2386 part 3 < 2%< 2%

*Polishing Value does not apply when the coarse aggregate is used in the 19mm

SMA, which is used as an intermediate (binder) course

SMA Designation 13mm SMA 19mm SMA

Composition of Stone Matrix Asphalt


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SMA Designation 13mm SMA 19mm SMA

Nominal Aggregate size 13mm 19mm

Nominal layer thickness 40 50mm 45 75mm

IS sieveCumulative % passing

by weight of total

aggregates

Cumulative %passing by weightof

total aggregates

26.5 - 100

-

13.2 mm 90 - 100 45 - 709.5 mm 50 - 75 25 - 60

4.75 mm 20 - 28 20 - 28

2.36 mm 16 - 24 16 - 24

1.18 mm 13 21 13 - 21

0.6 mm 12 18 12 - 18

0.3 mm 10 - 20 10 - 20

0.075 mm 8 - 12 8 - 12

515.Mastic Asphalt


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Mastic Asphalt is used as a wearing course for bridgedecks and heavily stressed intersections in urban areas. Thisis a homogeneous mixture of well graded aggregates,limestone powder filler and a hard grade bitumen (10 to 20

pen) to yield a plastic and void less mass, which whenapplied hot can be trowelled and floated to form a very denseim ermeable surfacin .

Binder content is 14 to 17%.Normal thickness is 25 to 50mm.

Hardness number (IS: 1195-1978): Mastic Asphalt shall have ahardness number of 60 to 80 at the time of manufacture at

25C prior to the addition of coarse aggregate and 10 to 20 at25C at the time of laying after the addition of coarse

aggregate.

Table 500 29, Requirements for physicalproperties of binder


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PropertyTest

methodRequirements

Penetration at 25C IS:1203 15 5

Softening Pont, C IS:1205 65 10

properties of binder

C Max

IS:1212 2.0

Solubility in trichloroethylene,% by mass Min

IS:1216 95

Ash, (mineral matter) by massMax IS:1217 1.0

Table 500 30, Grade and thickness of Mastic AsphaltPaving and Grading of Coarse aggregate


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ApplicationThickness range

(mm)

Nominal size ofcoarse

aggregate (mm)

Coarseaggregate, % by

mass of totalmass

Roads andCarriageway

25 - 50 13 40 10

Heavily stressed

g g gg g

areas .e.

junctions andtoll plazas

40 - 50 13

Nominal size of coarseaggregate

13mm

IS Sieve (mm) Cumulative % passing by weight

19 100

13.2 88 - 100

2.36 0 - 5

Table 500 31, Grading of fine aggregate(inclusive of Filler)


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IS SievePercentage by

weight of aggregate

Passing 2.36mm but retainedon 0.600mm 0 - 25

Passin 0.600mm but

( )

retained on 0.212mm

Passing 0.212mm butretained on 0.075mm

10 - 30

Passing 0.075mm 30 - 55

Filler shall be limestone powder passing 0.075mm sieveand shall have a calcium carbonate content of not less than80%by weight when determined in accordance with IS: 1514


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73/89

501.6 COMPACTION

Commence From Edges And Progress

Towards Centre

Initial Breakdown Rolling 8 To 10 T Smoothee o er

Intermediate Rolling 8-10 T Dead Wt. OrVibratory Roller, Pneumatic Tyred Roller :12-15 TWt. 5.6 Kg/Sq.Cm Pressure.

Finished Rolling 6-8 T Smooth WheelTandem Roller


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Recommended Frequency and Amplitude

For Vibratory Compaction

Lift frequency amplitude

Thin maximum low

thick minimum high

The frequency of vibration is the number of complete cycles thatthe eccentrics rotate per minute. The faster the rotation of the eccentrics,the greater the frequency of vibration.


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Some vibratory rollers can operate at only one frequency or havea very limited selection of frequencies.

Other vibratory rollers can alter the frequency of the applied loadbetween 1600 and 4000 vibrations per minute.

Frequencies below 2000 vibrations per minute are not normallyacceptable to compact asphalt mixtures.

If the width of the roller drum is 2.1 m (7 ft), only two passes ofthe roller are needed to cover the 3.7 meter (12 ft) wide lane, including a150 mm (6 in) overhang at each edge of pavement.

A roller that is 1.8 m (5.9 ft) wide cannot cover the complete 3.7meter (12 ft) wide lane in only two passes.

Three passes of the 1.8 m (6 ft) wide roller would be necessary toproperly compact the lane.

If the roller had drums that were 1.5 m (5 ft) wide, three passes ofthe roller would be required, similar to the roller with the 1.8 m (6 ft) widedrums.

A 1.4 m (4.5 ft) drum needs four passes for one coverage.For thick lifts, first pass should be about 0.30 m (1 ft) in from edge to

prevent shoving.


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AmplitudeAmplitude

Normal values of nominal amplitude range from 0.25 to 1 mm (1/100 to1/32 in).

Some rollers can operate at only one fixed amplitude, while others have

high and low amplitude positions.

Typically as the layer thickness increases, it is often advantageous toincrease the nominal amplitude applied to the asphalt mix.

Unless high amplitude is needed to achieve a particular density level,the vibratory roller should be operated in low amplitude.

Ask: Does changing frequency change the compaction effort? (Yes. 10-12

vibrations/ft. Never less than 10.)


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Impact SpacingImpact Spacing

High FrequencyHigh FrequencyLow FrequencyLow Frequency

DIRECTION OF TRAVELDIRECTION OF TRAVEL

FrequencyFrequency

ONE ROLLER PASS


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1122

CROWNCROWN22--lanes @lanes @

O O SS

44

33

55

66

(12 ft)(12 ft)

Drum WidthDrum Width= 1.8 meters= 1.8 meters

6 ft6 ft

The capabilities of each type of roller vary,


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however, with mat thickness, mix temperature, mixdesign and environmental conditions.In addition, the number of passes required

depends on the position of the rollers in the roller

train. A test strip aids us in this decision process.

,

which can tell us whether the designed mix isresistant to rutting. It should be able to proof test themixes and tell us whether a mix satisfies a definitecriteria and passes or fails the torture test. This test

should be a laboratory test method so that it can beused on designed mixes, and it should be a simpletest method so that it can be used routinely by the

folks who actually build our pavements.

Rolling


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Rolling is a highly technical and skillful operationduring which poor judgment is likely to result in failure toachieve the required compaction. Although various

guidelines describing sound engineering practices forcompaction procedures are available each case will have itsunique features and there can be no substitute forexper ence n ac ev ng success u compact on.

Initial or breakdown RollingIntermediate Rolling

Finish Rolling

Rolling sequence: Transverse joint, Longitudinal joint,Lower edge rolling, Break-down rolling, Intermediate

rolling(vibratory) Finished rollin


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2.25

2.3

2.35

2.4

Relationship of density with passes

sity

PASSINGDENSITY

Use 3 to 4 passes

2

2.05

2.1

2.15

.

0 2 4 6 8

Too

many

passes

Den

No of Passes


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Table 900 2,Maximum permitted number of irregularities


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Surfaces ofcarriageways and

paved shoulders

Surfaces of laybys,service roads and all

bituminous courses

Irregularity 4mm 7mm 4mm 7mm

Length(m) 300 75 300 75 300 75300

75

National highways/

Expressways 20 9 2 1 40 18 4 2

Roads of lowercategory

40 18 4 2 60 27 6 3

The maximum allowable difference between the roadsurface and underside of a 3m straight edge when


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For pavement surface (bituminousand cement concrete)

3mm

placed parallel with, or at right angles to the center lineof the road at points decided by the Engineer

For bituminous courses 6mm

For granular sub-base or basecouses

8mm

For sub-base under concrete

pavements 10mm

903.2 Tests on Earthwork for embankment, sub-gradeconstruction and cut formation


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Test type As per codeFrequency of

testing

Sand Content IS:2720 part 42 per 3000 cubic

meters

Plasticity IS:2720 part 52 per 3000 cubic

meters

Density IS:2720 part 8

2 per 3000 cubic

meters

DeleteriousContent

IS:2720 part 27As and whenrequired by

engineer

Moisture Content IS:2720 part 21 test per 50 cubic

meter

Soaked/ un-soaked

CBR

IS:2720 part 161 per 3000 cubic

meters

Important quality Control Tests for sub base andbase


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Test Type of construction Frequency (min)

Gradation

(IS:2386 part1)

Granular Sub Base

WBM/ WMM

1 per 200cum

1 per 100cum

Atterbergs limits

(IS:2720 part 5)

Granular Sub BaseWMM on aggregates

WBM(for binding material)

1 per 200cum1 per 100cum

1 per 25cum

Moisture content

(IS:2720 part 2)

Granular Sub Base

(prior to compaction) 1 per 250sqm

Density (IS: 2720 part28) for compacted layer

Granular Sub Base 1 per 500sqm

CBR (IS:2720 part 16) Granular Sub Base As required

AIV (IS:2386 part 4) WBM/ WMM 1 per 100cum

FIV and EIV

(IS:2386 part 1)WBM/ WMM 1 per 200cum

Important quality Control Tests for Prime Coatand tack coat


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Test Reference Frequency (min)

Quality of binder IS:73, IS:217 andIS: 8887

As applicable in thecodes

Temperature forapplication - At regular intervals

Rate of spread of

binder

-One test per 500m2

and not less than 2

per day

Tests for Bituminous Macadam

Test type As per code Frequency of testing


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Quality of binderIS:73, IS:217 and

IS: 8887As applicable in the codes

Aggregate Impact Value LosAngeles Abrasion Value

IS:2386 part 4 1 test per 50 cubic meter

Flakiness and ElongationIndex

IS:2389 part 1 1 test per 50 cubic meter

Initially 1 set of 3 specimens for each

tr pp ng a ue :9241 source an su sequent y y c ange nquality of aggregates

Water Absorption IS:2386 part 3 - DO -

Water Sensitivity of mix AASHTO T83 In case of failure in stripping test.

Soundness IS:2386 part 5 1 test by each method for each source

Binder content and grading - 2 tests per day per plant

Density - 1 test per 250 M2

Tests for DBM, SDBC and BCIn addition to the tests on BM


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Test type As per code Frequency of testing

Sand Equivalent Test Is:2720 part 37 As required

Plasticity Index IS:2720 part 5 As required

Polished Stone value BS:812 part114 As required for SDBC and BC

Mix grading -

1 set of tests on individual constituents and

mixed aggregate from the dryer for each 400T of mix subject to a minimum of 2 per plant

per day

Stability of MixMS 2 of Asphaltic

Institute3 Marshall specimens for 400M3 subject to a

minimum of 2 per day per plant

Control of bindercontent and grading

- 1 test for 400M3 subject to a minimum of 2

per day per plant

Rate of spread of mixedmaterial

-Regular control through checks on the

weight of mied material and layer thickness.

important aspects in road construction

Documents