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IRC 29-1988

SPECIFICATIONFOR

BITUMINOUS CONCRETE

(ASPHALTIC CONCRETE)

FORROAD PAVEMENT

(FirstRevision)

THE INDIAN ROADS CONGRESS

1996

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SPECIFICATION

FOR

BITUMINOUS CONCRETE

(ASPHALTIC CONCRETE)

FOR

ROAD PAVEMENT

(FirstRevision)

Published by

THEINDIAN ROADS CONGRESS

Jamnagar House, Shabjahan Road,

NewDelhi-hO011

1996PriceRs.32

(Plus packing & postage)

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IRC : 29-1988

First published

Reprinted

First RevisionReprinted

Reprinted

December, 1968

March, 1977

March, 1989August. 1996

Februaiy, 2000

(Rightsof Publication andof Translation are Reserved)

Printedat DEEKAY PRINTERS, New Delhi- 110015(500 copies)

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IRC: 29-1988

CONTENTS

ClauseNo. Page

I. Introduction I

2. Scope 2

3. Design Criteria 24. Materials

5. Mix Design ... 6

6. Construction ... 7

7. Opening to Traffic ... 12

8. Controls

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I. INTRODUCTION

The erstwhile Bituminous Pavement Committee in theirmeeting heldat New Delhi on 30th November, 1979 constituteda Sub-group consisting of SfShri N. Sivaguru, P. J. Mehta,Lt. Col. Avtar Singh, Dr. Arun Kumar and a representative each

from C.P.W.D. and I.A.A.I. to go into the question of revisionof IRC: 29-1968 Tentative Specification for 4 cm AsphalticConcrete Surface Course. The Sub-group held its meetings on16th July and 9th December, 1980. The report of the Sub-groupwas considered by the Bituminous Pavement Committee in theirmeeting held at Madras on the 12th December, 1985 which reques-ted Shrj R.S. Shukia to take action to revise the draft further.This draft wasdiscussed by the Bituminous Pavement Committeeintheir meeting held on the 13th March, 1987. The Committee

constituted a working group under the Convenorship ofShri R.K.Saxena for finalising the draft.

The draft prepared by the workinggroup was consideredby the newly constituted Flexible Pavement Committee (person-nel given below) in their meeting held at Madras on the 30thSeptember, 1988. The Member-Secretary ofthe Committee wasauthorised to finalise the document on the basis ofthe commentsmade by the members.

Sekhar MukherjeeAnil T. PaidT. H. PeshoriR. K. SaxenaA. Sankaran

R. S. Shukia

N. SenRep, ofBharatPetroleum

Corporation Ltd.(A.D. Nayak)

ThePresidentIRC(3. M. Maihotra)

SPECIFICATION FOR BITUMINOUS CONCRETE(ASPHALTIC CONCRETE) FOR ROAD

PAVEMENT

Co,n,enor

Member-Secretary

Prof. C. G. Swaminathan

P. Bhaskatan

R. T.Atre

G. R. AmbwaniDr. M. P. DhirR. A. GoelDr. A. K. GuptaM. B. Jayawant

P. K. LauriaDirector, HRS MadrasRep. ofJ.O.C.

(S. S. Das Gupta)Rep.ofHindustan Petroleum

CorporationLtd.,(R. C. Arora)

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Rep. of I .T.T. Kharagpur The DG (RD) (K. K. Sarin)(Dr. B . B . Pandey) The SecretaryIRC

(NinanKoshi)

The revision as finalised by the Member-Secretary, FlexiblePavement Committee was considered and approved by theHighways Specifications and Standards Committee in theirmeeting held at NewDelhi on the 24th November, 1988.

The Specification got the approval of the ExecutiveCorn-niittee by circulation and theCouncil in their 124th meeting heldat Madras on the 10th December, 1988.

A Tentative Specification for Bituminous Concrete (Asphal-tie Concrete) for Airfield Pavements has also been preparedand published separately as IRC 105-1988.

2 . SCOPE

2.1. This specification deals with the basicoutline for thedesign, construction and controls needed while layingbituminous

concrete (earlier termed asphaltic concrete inIRC: 29-1968) mixas wearing course on highway pavements.

2.2. Bituminous concrete shall be used as a wearing course,and normally itshould notbe laid directly over Water BoundMacadam or any granular base or bituminous course other thandense bituminous macadam (IRC 94-1986 Specification forBituminous Macadam).

2.3. The work shall consist ofconstructing a single layerof 25 rnm40 mm/50 mm thick bituminous concrete with materialcomprising mineral aggregates and appropriate binder mixed ina hot-mix plant and laid witha paver on a previously preparedbituminous/cement concrete base to the requirements of thespecifications described herein and conforming to the lines,grades and cross sections.

3. DESIGN CRITERIA

3.1. Being high cost specification, bituminious concreteniixes should be properly designed so as to satisfy certain criterianeeded to ensure adequate stability, satisfactory performanceand durability. The mix as designed and laid should satisfy therequirements given in Table 1 based on Marshall method ofdesign.

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TASLE 1. R E Q U L K E M E N IS o~BITuMINoUsCONCRETE Mix

SI. No. Description Requirement

1 . Marshall stability (ASTM DesignationD 1559) determined on Marshallspecimens, compacted by 750 compactionblowson each end, in kg (minimum) 650

2. Marshall flow (mm) 2 4

3. Per cent voidsin mix 3 5

4. Per cent voids in mineral aggregatefilledwith bitumen 7585

5. Per cent voids in mineral aggregates (VMA) 13166. Bindercontentper cent by weightoftotal

mix (to bedecided on Marshall designmethod) 5 7

Notes

1 . It is suggestedthat higher stability values consist with other require-ments should be achieveda~far as possible.

2. At busstops,parking areas and round abouts, stability of750kg

and near minimum flow valueshould beadopted.3. The attempt should be to have well graded aggregate and the

per cent voids in themix closer to the lowerlimit.4. The binder content in the case ofslag is likelyto exceed the limit

indicated in the Table.

3.2. The choice ofthickness of the bituminous concrete viz.25 mmJ4O mm/50 mm shall be decided on its functional require-ment for the traffic plying on the highway.

4 . MATERIALS

4.1. In order to satisfy the requirements spelt out inclause 3 , the bituminous concrete mixshall consist of coarseaggregate, fine aggregate and filler in suitable proportions andmixed with sufficient binder. The materials shall satisfy thephysical requirements described hereinafter.

4.1.1. Bitumen: Bitumen shall be paving bitumen ofsuitable penetration grade within the range ofS 35 to S 90 orA 35 to A 90(30/40 to 80/100) as per Bureau of Indian StandardsSpecifications for PavingBitumen lS 73. The actual grade ofbitumen to be used shall be decided by the Engineer, appropriateto the region, traffic, rainfall and other environmental conditions.

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4.1.2. Coarse aggregate : Coarse aggregate shall becrushed material retained on ~.36 mm sieve and shall be crushedstone, crushed slag or crushed gravel (shingle). It shall be clean,strong, durable, of fairly cubical shape and free from disinte-grated pieces, organic or other deleterious material and adherentcoatings The aggregates shall preferably be hydrophobic andol low porosity. If hydrophillic aggregates are to be usedbitumen shall preferably be treated with antistripping agentsof approved quality in suitable doses. The aggregate shallsatisfy the physcial requirements set forth in Table 2.

lsaLF 2. Pf~vsIcALREQUIRE~1EMTSo, COARSE AGGREGATE

Test

Aggregate Impact Value*

Maximum(Per cent) Test method

30 IS 2386 (Part IV)or

Los Angeles Abiasion Value* 40 IS 2386 (Part IV)f:lakiness Index 25 IS : 2386 (Part I)Stripping Value 2~5 IS 6241Waterabsorption@ I IS : 2386 (Part Ill)Soundness

(i) Loss with sodium sulphate 5 cycles 1 2 IS 2386 (PartV)(ii) Loss with magnesium sulphate 5 cycles 1 8 IS 2386 (Part V)

Notes

I. ~Aggregate shall satisfy requirements of either ofthetwo tests.2. ~uWater absorption upto a maximum of2 per cent can be permitted

in exceptional cases only.3. Ifcrushed slagis used, it shall be made from air cooled blast furnace

slag. It shall be of angularshape, reasonablyuniform in qualityand density and generally free from thin, elongatedand soft pieces,

dirt or other deleteriousmaterials. The unit weight of the crushedslag shall not heless than 1120 kg per m~and the percentageofglossy materials shall not be more than 20. It should also complywith the following requirements

Ii) Chemicalstability To comply with requirements of appendixofBS: 1047

(ii) Sulphur content Maximum2 percent(iii) Water absorption Maximum 10 per cent

The aggregate shallnot contain more than 6 per cent by

weight offlat/elongated pieces(flat piece is one having ratio ofwidth/thickness more than 4; elongated piece is where the ratiolength/width is more than 4).

4.1,3. Fine aggregate: Fine aggregate shall be the fractionpassing 2.36 mm sieve and retained on 75 ~imsieve, consisting

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of crusher run screenings, natural sand or a mixture ofboth. Itshall be clean, hard, durable, uncoated, dry and free from anyinjurious, soft orflaky pieces and organic or other deleterioussubstances.

4.1.4. Filler : The requirement of filler in bituminousconcrete shall normally be met by the material passing75

1 . sm

sieve in fine aggregate, if any. in case the fine aggregate isdeficient in material passing 75 ~sm sieve, extra filler shall be

added. The filler shall be an inert material, the whole ofwhichpasses 600 jzm sieve, atleast 90 percent passing 150 ~m sieveandnotless than 70 percent passing 75 ~m sieve. The filler shall bestone dust, cement hydrated, lime, fly ash or any other approved

non-plastic mineral matter.

4.2. Aggregate Gradation

Trueand representative samples of the mineral aggregates,including mineral filler proposed to be used on the specificjobshallbe tested in the design laboratory and proper blend of theaggregates shall be worked out so that the gradation offinalcomposition shall conform to the grading set forth in Table 3.

Forcompacted layer thickness of 25 mm, grading I

shall be used.For40 mm thickness, grading 2 and for 50 mm bitumen gra-ding 2 and grading 3 can be used.

TARLF 3. AGGREGATE GRADATION

Per cent by weight passing thesieve

Sieve designation Grading I Grading 2 Grading 3(For 25 mm (For 40 mm (For 50 mm

thick & 50 mm thick course)course) thick coursej

26.5 mm 10022.4 mm 100 82 9813.2 mm 100 80 100 608311.2 mm 90-100 75-95 55 775.6

mm 6 0 80 5 5 7 5 4 5 6 5

2.36 mm 40 55 40-55 40 55600 ~m 20-30 20 30 20-30300 ~sm 15-25 1 5 2 5 1 5 2 5150pm 10-20 10-20 10 20

75 ~m 6 9 6 9 6 9

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5 . MIX DESIGN

5.1. Requirement of Mix

Apart from conformity with the quality and grading requi-rements ol individual ingredients specified, the mix shall meetthe requirements set fotth in Table I.

5.2. Binder Content

The binder content shall be so fixed as to achievetherequirements ofthe mixset forth in Table 1. Binder content maybe suitably fixed in the case of crushed slag. Marshall methodof design for arrivingat the binder content shallbe adopted.

5.3. Job Mix Formula

5.3.1. Whilethe laboratorymixdesign gives thedifferent pro-portionsofthe mineral aggregatecombinations in terms of indi-vidual, sieve sizes ofaggregates, blending ofaggregates (each size

having within it a range of individual sieve sizes) would be neces-sary. This blending ratio is obtained on a weight basis, givingtheper cent weightsofthecoarse aggregates, fineaggregateand fillertogive the ultimate aggregategradation. It canalso be proportioned

on a volumetric basis based on the unit weight or bulk density ofthe aggregates supplied. This mineral aggregate combinationtogether with the corresponding optimum bitumen content asdetermined in the Laboratory, constitutesthejobmixformula forimplementation during construction.

5.3.2. Whileworking outthe job mix formula, it shall beensured that it is based on a correct and truly representativesampleofmaterials that will actually be used inthe work so that

this formula could be adhered to in practice on that specificconstruction project and that the mixand itsdifferent ingredientssatisfy the physical and strength requirements ofthese specifica-tions.

5.3.3. Along withthejob mix forniulaproposed to he usedon the work, the followingdetails shall be given

(i) Sour~eand locationofall materials.

lii) Proportions ofall materials expressed asfollows where eachis applicableBinder As percentage by weight of

total mixCoarse aggregate As percentage by weight ofFine aggregate total aggregate includingMineral filler mineralfiller

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ciii) A single definite percentage passing each sieve for themixedaggregate.

(iv~The results oftests enumerated in Table I as obtained for thejobm ix formula.

(v) Tests results of physical characteristics of aggregates to beused.

5.3.5. The approved job mix formula shall remain effectiveunless and until the same is modified and reapproved by theEngineer.

5.3.6. Should a change in the source of materials be pro-posed, a new job mix formula shall be established and got appro-ved from the Engineer before actually using the materials.

5.4. PermissIble Variations from the Job Mix Formula

Proper proportioning of materials in accordance withtheapproved job mixformula and producinga uniform mixin actualpractice shall be ensured. The permissible variations of the indi-vidual percentages of the various ingredients in the actual mixfrom the job mixformula may be within the limits as specified inTable4. These variations are intended to apply to individual

specimens taken for quality control tests.TABLE 4. PERMIsSIBLE VABIATIONS FROM THEJoa Mix FORMULA

SieveDescription

Permissible variationby weight to totaaggregate (per cent passing)

I

Grading 1 Grading 2 Grading 3

26.5mm 22,4mm 813.2mm 8 811.2 mm & 5.6 mm 7 7 72.36mm 4 4 4600~im 3 3 3

150 ~m and 7 5 ~ni I 1 1Bindercontent + .3 .3 ~ .3

6. CONSTRUCTION

6.1. Weather an d Seasonal Limitations

Thework oflaying shall not be taken up during rainy orfoggy weather or when the base course is damp orwet or during

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ust storm or when the atmospheric temperature in shade isOC or less.

6.2. Preparation of Base

The base on which bituminous concrete is to be laid shalle prepared, shaped and conditioned to the specified levels,rade and crossfall (camber) in accordance with well establishednd accepted practice. The surface shall be thoroughly sweptnd scraped clean, freeofdust and other foreign matter.

In case the existing baseis extremely irregular and wavy,t would be advisable to provide a profile corrective course ofppropriate type (i.e. bituminous levelling course) of adequate

hickness to avoid an excessive use of this costly wearing

ourse.In case theexisting base is in distressed condition, it is

dvisable to provide suitable remedial measures prior to layinghis costly wearing course.

6.3. Tack Coat

6.3.1. This work shall consist of application of a singleoat of low viscosity liquid bituminous material to the prepared

asepreparatory to another bituminous construction overit.6.3.2. The binder used for tack coat shallbe bitumen of a

uitable grade appropriate to the region, traffic, rainfall andther environmental conditions and conforming to IS : 73, 217r 454, or 8887 as applicable, or any other approved bituminous

aterial.

6,3.3. The surface on which the tack coat is to be appliedhall be cleared ofdust and any extraneous material before the

pplication of the binder, by usingamechanical broom or anyther approved equipment/method as specified.

6.3.4. Binder shallbe heated to the temperature appro-riate to the grade of bitumen used and sprayed on the base at

he rate specified in Table 5. The rate of spread is in terms oftraight run bitumen.

TAStE 5, RATs O~APPLICATTON OF TACK COAT

ormal

TypeofSurface~

Bitumen quantityin kg per10 sq. metre area

bituminoussurface 5.0 to 5.5ry andement

hungry bituminous surfaceconcrete pavement

6.0 to 7.57.5

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63.5. The binder shall be applied uniformly with the aidol either self propelled or towed bitumen pressure sprayer withself heating arrangement and spraying nozzles arrangementcapable ofspraying bitumen at specified rates and temperatureso as to provide a uniformly unbroken spread of bitumen

6.3.6. The tack coat shall be applied just ahead of the on-coming bituminous construction.

6.4. Preparation an d Transport of Mix

6.4.1. Hot mix plant of adequate capacity and capable ofproducing a proper and uniform quality mix shallbe used forpreparing the mix. The plant may be either a weigh batch typeor volumetric proportioning continuous or drum mix type. Theplant shall have coordinated set of essential units capable ofproducing uniform mix as per the job mix formula such as

(a) Cold aggregate feed system for providing blended aggregate in thecorrect proportion (called cold Binspacefeed arrangement).

tb) Rotatingcylindricaldryer dium fitted with suitable burner capable

of heating the aggregate to the required temperaturewithout anyvisibleunbumnt fuel or carbon residue on the aggregate and toreduce the moisture content ofthe aggregateto thespecified mini-mum level.

(c) The dryer Units shall be tilled ~ hIt appro~ed type of thermometricinstruments at appropriate places so as to indicate or automaticaLlyrecordjregister the temperature of heated aggregate hcf~rc addingmixing thebinder.

C d) Gradation Control : Except in case of DrumMix Plant,

other two types of plants mentioned above shall have(i) A screeningunit for accurate sizing ofhot aggregate and

feeding the same to mixing unit by weight or volumecontrol as per the specifiedjob mix formula.

(ii) Paddle mixer unit shall be capable of producing a homo-geneous mix with uniform coating of all particles ofmineral aggregate with binder.

(c) In case ofdrummix plant, thecold feed system shall havevariable speed belt conveyors/or other suitable devices for

regulating the accurate proportioning of aggregate into aneven feed flow automatically from central operatingcentralcabin.

f) Bitumen Control Unit: Capable ofmeasuring,.nleteringandspraying required quantity of bitumen at specified tempera-ture with synchronisation ofbitumen and aggregate feed.

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(g) Filler System A fines feeder system suitable to receivebagged or bulk supply of filler material and for its incorpo-rationintothe mix in the correct quantity.

(h) Dust Control : A suitable built in dust control equipmentfor the dryer tocontain the exhaustof fine dust intoatmos-phere for environmental control, wherever so specifiedbythe Engineer.

(if Suitable Auxilliary Bitumen boiler of adequate capacity withselfheating arrangement and temperature control device.The boiler should be fitted with temperature indicatinginstruments,

6.4.2. The temperature of binder at the time of mixinghall be in the range of 150177Cand of aggregates in the

range of 153163C. Provided also that at no time shallhe differencein temperature betweenthe aggregates and binderxceed 14C.

6.4.3. Mixing shallbe thorough to ensure that a homo-eneous mixture is obtained in which all particles of the mineral

aggreates are coated ttniformly.

6.4.4. The n,Lx shall he transported from the mixing plant

to the point ofuse in suitable tippervehicles. The vehicles emp-loyed fortransport shall be clean and be covered intransit ifrequired by site conditions.

6.5. Spreading of the Mix

6.5.1. The mix transported from the hot mix plant to thesite shall he spread by means of a self propelled mechanicalpaver with suitable screeds capable of spreading, tamping and

finishing the mixto specified grades, lines and cross sections.Paver Finisher shall have the followingessential features

(a) Loading hoppers and suitable distributing mechanism.

(It) Hydrostatic drive/control for all drive,

C c) Hydraulically extendable screed for appropriate widthrequirement.

Cd) Thescreed shall have tamping and vibrating arrangement

for initial compaction to the layer as it is spread withoutrutting orotherwise marringthe surface. It shall have ad-justable amplitude and infinitely variable frequency. Itshould preferably have screed ofadequate width to lay themix on two lane carriageway in one operation.

fe) Necessary controlmechanismin the paver to ensure that thefinished surfaceis free from surface blemishes.

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If) Electronic sensing device in tli~paver for automatic Level-ling and profile control within thespecified tolerances.

Ig) Internal heating arrangement for the screed.

6.5.2. However, in restricted locations and in narro~~widths where the available plant can not be operated, manuallaying of the mix may be permitted. Themix should he spreadin such a manner that after compaction, the reqttired thickness ofwearing course is uniformly obtained.

6.5.3. Longitudinal joints and edges shall be constructedtrue to the delineating lines parallel to the centre line 01 theroad. Longitudinal joints shall be offset by at least 150 mmfrom those in the lower course All joints, longitudinal, tran-sverse and construction, shall be cut vertical to the full thicknessof the previously laid mix and the cut surface painted with hotbitumen before placing fresh material.

6.6. Rolling and Compaction

6.6.1. After spreadingby paver, the mixshall be thoroughlycompacted by rolling with a set of rollers moving at a speed ofnot more than 5 km per hour, immediately followingcloseto thepaver. The initial or breakdown rolling shall bewith 8 to 12tonne three wheeled steel roller and the finished rolling with 8to 10 tonne tandem roller. Before finishing with the tandemroller, breakdown rolling shall preferably be followed by anintermediate rolling with a smooth wheel pneumatic roller of

1 5 to 30 tonne capacity having a tyre pressure of 7 kg/cm2. All

the compaction operations ie. breakdown rolling, intermediaterollingand finished rolling can be accomplished by using vibra-

tory roller of 8 to 10 tonne static weight. During the initial orbreakdown rolling and finished rolling, the vibratory systemshall be switched off. The joints and edges shall be rolled witha 8 to 10 tonne three ~xheeled static roller,

The wheels of roller shell he kept moist to prevent the mixfrom adhering to them. But in no case shall fuellubricating oilbe used for this purpose nor excessive water poured on thewheels. Rolling shall commence longitudinally from edge andproceed towards the centre, except that on superelevated points,it shall progress from the lower to upper edgeparallel to thecentre line of the pavement. The roller shall proceed on thefresh material with rear or fixed wheel leading so as to minimisethe pushing ol the mix and each pass ofthe roller shall overlapthe preceeding one by half the width of the rear wheel.

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6.6.2. Rolling operations shallbeconductedwhenthe mixis neither too hot nor too cold so thatshovingor haircracksmaybe eliminated. Rollingshall becontinued till the densityacheived is at least 98percentofthatof Laboratory MarshallSpecimenandall roller marksareeliminated.

7. OPENINGTOTRAPflC

Traffic may be allowed after completion of the finalrollingwhen the mix has cooled down to the surroundingtemperature.

5. CONTROLS

8.1. Adequatequalitycontrol at every stage of work isessentialandassuch a fieldlaboratory must be set up to ensurethe following controls.

8.1.1. Periodicsieveanalysisofeachtypeof the aggregateatthecold feeder should bemadeto seethat theyadationotthejobmixformula isachieved. The number ofsamples per daywoulddepend upon thenumberofbulksupplyof the aggregatesmade in a day at the plant site. The physical propertiesasrequiredin Table2 shallbedetermined at the rate of one testeach for every 50100m5 of aggregates. Filler gradingshallbetested attherate of 1 test for every S in5offiller.

8.1.2. Formix grading one set of tests on individualconstituents and mixed aqregate from thedryer for each 100tonnes ofmixsubjectto a minimum oftwo sets per plant perdaywill bedone.

Periodiccheck ofthe aggregate at the gradation controlunit (iftheplant is fitted with one)or atthehotbin gatesshouldbemade to seethattheproportionoftheaggregates as specifiedinthe jobmix formula is compliedwith.

8.1.3. Periodiccheck onpenetration and softening pointof thebindershould alsobe done inthemanner specifiedIn IS:1203and lS: 1205.

8.l.& It shall be ensured that. the aggregates are nottotallywet in whichcase Itwouldeffect theoutput of the plantadversely. Thetemperaturemeasuring deviceInstalledat theendofdryer should becheckedperiodicallyto seethat the aggregatetemperature neverexceeds l6?C. Atoleranceupto lOt on thelower side could bepermitted.

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8.1.5. The bitu men temperature should be well within thelimits specified. The viscosity of heated bitumen shall be bet-ween 150 and 300 centi stokes for which the normal temperaturerange for paving bitumen is I 50-l77C.

8.16. At no time, the differencein temperature of aggregateand bitumen should exceed 14C.

8.1.7. At least one sample for every 100 tonnes of bitu-minous mix discharged at the pugniill chute shall be collectedand the followingtests done subject to a minimum of two setsbeing tested perplant per day.

lit 3 Marshall specimens shall becompacted and tested for thestability flow value, voids content and density. The averagevalueshould closely follow theLaboratory design value,

(ii) Bitumen shall be extracted from about 1000 gramso fthe mixand bitumen contentdetermined.

(iii) A sieve analysis of the aggregates after the bitumen i sextracted, shall be done and the gradationdetermined.

8.1.8. The temperature of the mix at the time of laying

shallnot exceed 160Cand shall not be less than 120CC. Careshould be taken to ensure completion ofcompaction before thetemperature falls below the limit specified in para 8.2.

8.2. Rolling operation shall be completed in every respectbefore the temperature of the mix falls below 100C.

8.3. After the mix is compacted the thickness laid may bechecked by noting the depth of penetration of hot steel scale,

This shall also be correlated with the measured area ofthe sur-face laid and the total plant output ofthe mixin tonnes (as givenin the plant scale).

8.4. For every 500 m2 or less of compacted surface, one

field densitytest should be conducted to determine the densityof the mix as laid, compacted and finished. The bulkdensity offinished course shall not be less than 98 percent of the Laboratorydensity.

8.5. The longitudinal profile of the finished surface shallhe tested witha straight edge4.5 m parallel to the centre line andthe transverse profile with a camber plate. Any irregularitygreater than 6 mmshall be corrected. The longitudinal profile ofthe finished surface shalJ also be tested with a roughometer(

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profIlometer and it should be ensured that the roughness shall notexceed 2000 mm per kilometre.

8.6. Surface evenness requirements in respect at both the

longitudinal and cross profiles should be simultaneouslysatisfied.