ABOUT JOURNAL - Geosynthetica · 2020-05-04 · ABOUT JOURNAL Geosynthetics are now being...

ABOUT JOURNAL

Geosynthetics are now being increasingly used the world over for every conceivable application in civil engineering, namely, construction of dam embankments, canals, approach roads, runways, railway embankments, retaining walls, slope protection works, drainage works, river training works, seepage control, etc. due to their inherent qualities. Its use in India though is picking up, is not any where close to recognitions. This is due to limited awareness of the utilities of this material and developments having take place in its use.

The aim of the journal is to provide latest information in regard to developments taking place in the relevant field of geosynthetics so as to improve communication and understanding regarding such products, among the designers, manufacturers and users and especially between the textile and civil engineering communities.

EDITORIAL BOARD

• Dr. Dali Naidu Arnepalli, Assistant Professor, Department of Civil Engineering, IIT Madras

• Dr. K. Balan, Professor, Department of Civil Engineering, College of Engineering, Trivandrum

• Mr. Narendra Dalmia, Director, Strata Geosystems (India) Pvt. Ltd.

• Mr. S. Jaswant Kumar, Former Chief General Manager, National Highways Authority of India

• Ms. Minimol Korulla, Vice President-TMD, Maccaferri Environmental Solutions Pvt. Ltd.

• Mr. Tiru Kulkarni, Vice President – Marketing, Sales & Design, Garware Wall Ropes Ltd.

• Dr. Gali Madhavi Latha, Associate Professor, Department of Civil Engineering, Indian Institute of Science

• Dr. Satyendra Mittal, Associate Professor, Department of Civil Engineering, Indian Institute of Technology Roorkee

• Mr. Satish Naik, CEO, Best Geotechnics Pvt. Ltd.

• Dr. K. Rajagopal, Professor, Department of Civil Engineering, IIT Madras

• Dr. G.V.S. Raju, Engineer-in-Chief (R&B), Government of Andhra Pradesh

• Dr. G.V. Rao, Chairman, SAGES

• Ms. Dola Roychowdhury, Senior General Manager (Geosynthetics Division), Z-Tech (India) Private Ltd.

• Mr. T. Sanyal, Chief Consultant, National Jute Board

• Dr. U.S. Sarma, Director, Coir Board

• Mr. M. Venkataraman, Geotechnical Consultant

• Dr. B.V.S. Viswanadham, Professor, Department of Civil Engineering, Indian Institute of Technology Bombay

CONTENTSPage

FrOm EdiTOr’S dESk 2• StudiesonEffectsofPrestressingtheReinforcementontheBehaviourofReinforcedGranular

BedsOverlyingWeakSoil–R. Shivashankar and J. Jayamohan 3

• ConsolidationofLightlyOCClayswithPVDsasaPhaseChangeProcess–P. Ayub Khan, M. R. Madhav and E. Saibaba Reddy 14

• ImprovementofCharacteristicsofSandMixingwithNaturalCoirFiber–Joyanta Maity, Bikash Chandra Chattopadhyay and Siba Priyo Mukherjee 22

• InternationalGeosyntheticsSociety 28

• IGSNews 32

• IndianChapterofInternationalGeosyntheticsSociety 34

• ActivitiesofIndianChapter 38

• CalendarofEvents 41

• ProfileofInstitutionalMemberofIndianChapter 42

iNdiaN ChapTEr OF iNTErNaTiONal GEOSyNThETiCS SOCiETy

Indian Journal of Geosynthetics and Ground Improvement

Volume 2, No. 2 July 2013

Allcommunicationstobeaddressedto:The Member SecretaryIndianChapterofIGSCBIPBuilding,MalchaMarg,Chanakyapuri,NewDelhi–110021

Editor• Mr.V.K.Kanjlia,Member Secretary, Indian Chapter of IGS and Secretary, Central Board of Irrigation and Power (CBIP)associate Editors• Mr.A.C.Gupta,Treasurer, Indian Chapter of IGS and Director, Central Board of Irrigation and Power (CBIP)• Mr.UdayChander,Senior Manager, Central Board of Irrigation and Power (CBIP)

Subscription information 2013/ (2issues)Institutionalsubscription(Print&Online) :Rs.900/US$75Institutionalsubscription(OnlineOnly) :Rs.600/US$50Institutionalsubscription(PrintOnly) :Rs.600/US$50

Volume 2 v No. 2 v July 2013

From the edItor’s desk

InternationalGeosyntheticsSociety(India),approvedasIndianChapterby IGSCouncil inOctober1988, iscelebratingSilverJubileeof itsservicestotheIndianGeosyntheticsCommunity,thisyear.

TheSilver Jubilee occasionwould provide an opportunity to haveretrospectofgeosyntheticsacceptanceasconstructionmaterialanddeliberateonfutureprospects.

Today the use of geosynthetics is increasingly being accepted asconstructionmaterialindifferentfieldsofcivilengineeringnotonlyindevelopedcountriesbutalsointhedevelopingcountrieslikeours.Itsusefortheconstructionofdam,embankments,canals,approachroads,runways,railwayembankments,retainingwalls,slopeprotectionworks,drainageworks, river trainingworks,seepagecontrol,etc.due to their inherentqualities,isnowbeingwellrecognized.

Tomarktheoccasion,anInternationalSymposium“GeosyntheticsIndia’13”,andaSeminaron“GeosyntheticBarriers”,andanExhibition,arebeingorganizedinNewDelhiduring23-25October2013.

TheSeminar on “GeosyntheticBarriers”will focuson current new research topics forgeosyntheticbarriers,suchasgeomembranes,geosyntheticclay liners (GCLS),multi-componentGCLsandbituminousliners,theuseofthesebarriersinvariousapplicationsandthepracticalinclusionoftheseengineeredbarriersforlandfills,mining,coalcombustionresidualsitesandotherindustrialapplications.

IinviteyoualltoparticipateintheSilverJubileeCelebrations.

IalsotakethisopportunitytothankyouallforthesupporttoIndianChapterofIGS,andlookforwardtoyourassociationtoachievemanymoremilestones.

V.k. kanjliaMember Secretary

IndianChapterofIGS

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1. iNTrOdUCTiON

Theuseofgeosyntheticstoimprovethebearingcapacityandsettlementperformanceofshallow foundationshasproventobeacost-effectivefoundationsystem.Inmarginalgroundconditions,geosyntheticsenhancetheabilitytouseshallow foundations in lieuof themoreexpensivedeepfoundations.Thisisdonebyeitherreinforcingcohesivesoildirectlyorreplacingthepoorsoilswithstrongergranularfillincombinationwithgeosyntheticreinforcement.Inlow-lyingareaswithpoorfoundationsoils,thegeosyntheticreinforcedgranularbedcanbeplacedovertheweaksoil.Theresultingcompositeground (reinforcedgranularbed)will improvetheloadcarryingcapacityofthefootingandprovidebetterpressuredistributionontopoftheunderlyingweaksoils,hence reducing theassociatedsettlements.During thepast30years,theuseofreinforcedsoilstosupportshallowfoundationshasreceivedconsiderableattention.

Manyexperimentalandanalyticalstudieshavebeenperformed to investigate thebehaviourof reinforcedfoundation beds for different soil types (eg. BinqetandLee(1975),Shivashankaretal.(1993)).Severalexperimentalandanalyticalstudieswereconductedtoevaluatethebearingcapacityoffootingsonreinforcedsoil(eg.Shivashankaretal.(1993);ShivashankarandReddy(1998);MadhavilathaandSomwanshi(2009);AlamshahiandHataf(2009);Vinodetal.(2009)etc).

Itisnowwellestablishedthatgeosyntheticsdemonstratetheir beneficial effects only after considerably largesettlementswhichmaynotbeadesirablefeatureforshallow footings, pavements, embankments, etc. Infact, for the initialsettlements, thestrains in thesoilare insufficient tomobilize significant tensile load inthegeosynthetic.Thusthereisaneedforatechniquewhichwillallowthegeosynthetictoincreasetheloadbearingcapacityofsoilwithouttheoccurrenceoflargesettlements.Lovisaetal.(2010)conductedlaboratorymodelstudiesandfiniteelementanalysesonacircularfooting resting on sand reinforcedwith geotextile tostudytheeffectofprestressingthereinforcement.Itwasfound that theadditionofprestress to reinforcementresultedinsignificantimprovementintheloadbearingcapacityandreductioninsettlementoffoundation.

Inthispaper,resultsfromlaboratorymodeltests,finiteelement analyses and numerical simulations on asquarefootingsupportedbyaprestressedreinforcedgranularbed(PRGB)arebeingdiscussed.Themainpurposeofthisinvestigationistoevaluatetheeffectsof prestressing the reinforcement in improving thebearingcapacityofsquarefootings.Theparametersconsideredinthestudyarestrengthoftheunderlyingweak soil, thickness of granular bed,magnitude ofprestress,directionofprestressandnumberoflayersofreinforcement.Numericalanalysesareconductedusing

stUdIes oN eFFeCts oF PrestressING the reINForCemeNt oN the BehAVIoUr oF reINForCed

GrANULAr Beds oVerLYING WeAk soIL

r. ShivashankarDepartment of Civil Engineering, National Institute of Technology Karnataka, India

J. JayamohanDepartment of Civil Engineering, LBS Institute of Technology for Women, Thiruvananthapuram, Kerala, India

aBSTraCT

The effects of prestressing the reinforcement on the strength improvement and settlement reduction of a reinforced granular bed overlying weak soil are being investigated through a series of laboratory scale bearing capacity tests. The influences of parameters such as strength of underlying weak soil, thickness of granular bed, magnitude of prestressing force, direction of prestressing forces and number of layers of reinforcement are being examined. Finite element analyses are carried out using the FE program PLAXIS to study the effect of prestressing the reinforcement. Results obtained from finite element analyses are found to be in reasonably good agreement with the experimental results. A numerical model based on punching shear failure mechanism is envisaged. The Bearing Capacity Ratio (BCR) values predicted by the model are found to be in good agreement with the experimentally obtained BCR values.

Key words : Geogrid, Granular Bed, Prestress, Model Test, Finite Element Analysis

4 Indian Journal of Geosynthetics and Ground Improvement


the improvisedmodel of Shivashankar et al. (1993)andtheresultsarecomparedwiththoseobtainedfromthemodeltests.Anonlinearfiniteelementanalysisisconducted using the FE programPLAXIS version 8andtheresultsarecomparedwiththoseobtainedfromthemodeltests.

2. laBOraTOry mOdEl TESTS

The experimental programme reported herein, thatinvolvesaseriesoflaboratoryscaleloadtestsonmodelfootingsrestingonprestressedreinforcedgranularbeds,wascarriedoutusingthetestfacilitiesintheStructuralEngineeringLaboratoryofCivilEngineeringDepartmentattheNationalInstituteofTechnologyKarnataka,India.Detailsoftheexperimentalprogramme,testproceduresandanalysisoftestresultsarepresentedbelow.

2.1 materials

Thematerialusedforgranularbediswellgradedmediumsandandlocallyavailablesoiltermedas‘Shedisoil’isusedasweaksoilandpropertiesofbothsoilsaregiveninTable1.ParticlesizedistributioncurveofbothsoilsareshowninFigure1.TheShedisoilisusedintwoconditionsnamelymoist condition (termedasmoist soil orweaksoil1)andalsousedinsubmergedcondition(termedassubmergedsoilorweaksoil2).ThereinforcementusedisGeogridanditspropertiesaregiveninTable2.Thegeogridusedisasomewhatweakgeogridwithatensilestrength of only 7.68 kN/m, for purpose of laboratoryscalemodeltests.

Table 1:Propertiesofsandandweaksoilsusedinthemodeltests

property

ValueSand Weak soil

1 (moist soil)

Weak soil 2 (Submerged

soil)Specificgravity 2.61 2.32 2.32

Averagedryunitweightduringmodeltest(kN/m3)

16.60 16.00 16.00

Voidratioduringmodeltest

0.54 0.42 0.42

Water content duringmodeltest(%)

0 10 31.5

EffectivegrainsizeD10 (mm)

0.50 0.11 0.11

D60(mm) 1.30 0.155 0.155

D30(mm) 0.80 0.125 0.125

CoefficientofuniformityCu

2.60 1.41 1.41

CoefficientofcurvatureCc

1.00 0.92 0.92

FrictionangleΦ (degrees)

31.0 12 6

Cohesion(kPa) 0 10 5.5

Table 2:Propertiesofgeogridusedinthemodeltests

property ValueMassperunitarea(gm/m2) 730.00ApertureSize(mm) 8x6Thickness(mm) 3.30TensileStrength(kN/m) 7.68Extensionatmaximumload(%) 20.20Color BlackPolymer HD-Polyethyelene

Shedisoilsaredispersivesoilsandarepredominantlyfound in thewestern coast of peninsular India,whichreceivesheavyrainfallduringmonsoon.Theirstrengthreduces drastically under saturation condition.Manyfoundation and slope stability problems are reportedwherever this soil is encountered [Bhat et al (2008),ShivashankarandSetty(2000)].

Fig. 1:Particlesizedistributionofsandandweaksoilused

2.2 Test Setup

Theloadtestsareconductedinacombinedtestbedandloadingframeassembly.Thetestbedsarepreparedinaferrocementtankwhichisdesignedkeepinginmindthesizeof themodel footingtobetestedandthezoneofinfluence.Thedimensionsofthetankare750mmlengthx750mmwidthx750mmdepth.Themodelfootingisarigidmildsteelplateof100mmx100mmsizeand20mmthickness.ThefootingwasloadedbyahandoperatedJack of 10 kN capacity supported against a reactionframe.The load ismeasuredusingaprovingringanddeformationusingtwodialgaugesplaceddiametricallyoppositetoeachother.ThefigureofthetestsetupisshowninFig.2andphotographofthesameinFig.3.

2.3 preparation of Test Bed

Atfirsttheweaksoilisfilledintheferrocementtanktotherequiredlevelwithcompactiondonein layers,toachievethepre-determineddensity.Thensandisfilleduptothebottomlevelofreinforcementandcompacted.Thereinforcementisthenplacedwithitscentreexactlybeneaththe jack,andtheprestress isapplied.Then

5


sandabovethereinforcementisplacedandcompactedtothepre-determineddensity.Thedensitiestowhichthe soils were compacted are indicated in Table 1.Thecompactiveeffortrequiredtoachievetherequireddensityofboththesoilsisdeterminedbytrialanderror.Preparationofunderlyingsoilinallthetestsinvolvedcompactionofsoilusingarammer.Inthepreparationofgranularbed,thesandwascompactedusingasmallplatevibrator.

Tests are carried out with single layer and doublelayerofreinforcement.Intheliterature, it isreportedthatoptimumdepthofplacementof thefirst layerofreinforcementis0.2Bto0.5B(Bisthewidthoffooting)(Sharmaetal.2009).Thedepthofreinforcementfromthebaseoffootingisadoptedas0.5Bforallthetestswithsinglelayerreinforcement.Incaseofdoublelayerreinforcement,thedepthoftoplayeris0.25Bfromthebaseoffootingandthatofbottomlayeris0.5Bfromthebaseoffooting.

Theprestressappliedisequalto1%,2%and3%ofthe

tensilestrengthofthegeogridandisdistributedoverthreepulleys.InuniaxialprestressingtheprestressisappliedonlyintheX-directionwhereasinbiaxialprestressingitisappliedinbothXandYdirectionsasshowninFigs.4&5respectively.

Studies on Effects of Prestressing the Reinforcement on the Behaviour of Reinforced Granular Beds Overlying Weak Soil

Fig. 5:Biaxialprestressing

2.4 Testing procedure

Afterpreparingthebed,thesurfaceisleveled,andthefooting isplacedexactlyat thecentreof the loadingjacktoavoideccentricloading.Thefootingisloadedbyahand-operatedhydraulicjacksupportedagainstareactionframe.Aprecalibratedprovingringisusedtomeasuretheloadtransferredtothefooting.Theloadis applied in small increments.Each load incrementis maintained constant until the footing settlementis stabilized. The settlement ismeasured using twodial gauges and their average value is adopted.Thesettlementat the interfacebetween twosoils isdeterminedbymeasuringthelevelsatspecifiedpointsatregularintervalsonthesurfaceofweaksoilbeforeandaftereachtest.Thetesttankisemptiedandrefilledforeachtesttoensurethatcontrolledconditionsaremaintainedthroughouttheinvestigation.ThedetailsoftestingprogrammearegiveninTable3.

Under seriesA, tests are conductedonweak soil 1(moistsoil)andonweaksoil1overlainwithunreinforcedgranularbedofthicknessBor2B.UnderseriesB,testsareconductedonweaksoil1overlainwithreinforcedgranular bed of thickness B or 2B with single anddoublelayersofreinforcement.UnderseriesC,testsareconductedonweaksoil1overlainwithprestressedreinforced granular bed. The parameters varied are

Fig. 2:Testsetup

Fig. 3 :Viewoftestsetup

Fig. 4 :Uniaxialprestressing



ΔBCRSL= 2τ1/Q ...(2)

τ1 = Pptanfs ...(3)

ΔqSL = 2τ1/B ...(4)

Where Q=Bearingcapacityofunderlyingweaksoil

τ1=Totalverticalforcealongthepunchingshearfailureplaneduetoshearlayereffect

Pp=Forceduetopassivepressuredevelopedonthesidesoffailuresurface,actingnormally,perunitlength

fs=Angle of internal friction of granularmaterial.

Theaboveequationwasdevelopedforastrip footing.Inthepresentstudy,sinceasquarefootingisused,theequationismodifiedasgivenbelow

τ1 = Pp’tanfs ...(5)

ΔBCRSL = 4τ1/Q ...(6)

ΔqSL = 4τ1/B2 ...(7)

magnitudeofprestress,directionofprestress,numberof layers of reinforcement and thicknessof granularbed.SeriesD,EandFaresimilartoseriesA,BandCrespectively,exceptthattheunderlyingweaksoiliskeptsubmerged(termedasweaksoil2).Thelevelofwatertableismonitoredbyinstallingfourpeizometersinthetesttank.

3. NUmEriCal aNalySiS

Inthepresentstudy,loadingtestsonunreinforcedandreinforced granular beds are simulated numericallyby improvisingthemodelproposedbyShivashankaretal.(1993).Theyproposedapunchingshearfailuremechanisminwhichboththefootingandtheportionof the reinforced granular bed directly beneath thefootingareenvisagedtoactinunisontopunchthroughthesoftsoilunderneath.Theimprovementinbearingcapacity of a reinforced granular bed is consideredtocompriseofthreecomponentsnamelyShearlayereffect, Confinement effect andAdditional Surchargeeffect. These effects are represented in Fig 6, Fig7&Fig 8 respectively. Theyproposed the followingequationsforcomputingBearingCapacityRatio.

BCR=1+ΔBCRSL+ΔBCRCE+ΔBCRSE...(1)

WhereBCR=BearingCapacityRatio

ΔBCRSL,ΔBCRCE,ΔBCRSE = Improvement in bearingcapacity ratio due to shear layer, confinement andadditionalsurchargeeffectsrespectively

3.1 Shear layer Effect

Inshearlayereffect,theshearstressmobilizedalongthefailuresurfacedue to thepassivepressuredevelopedinsoilisconsidered(Fig6).Theequationproposedforstripfootingsis

Table 3 :TestingProgramme

Series Type Number of layers of reinforcement

Thickness of granular bed

direction of prestress

magnitude of prestress

A Weaksoil1(Moistsoil)

(Unreinforced)Granular bed onweaksoil1

-- -- -- ---- B&2B -- --

B Reinforcedgranularbedonweaksoil1 1&2 B&2B -- --C Prestressed reinforcedgranular bedon

weaksoil11&2 B&2B Uniaxial&

Biaxial1%,2%&3%

D Weaksoil2(Submergedsoil)

(Unreinforced)Granular bed onweaksoil2

-- -- -- ---- B&2B -- --

E Reinforcedgranularbedonweaksoil2 1&2 B&2B -- --F Prestressed reinforcedgranular bedon

weaksoil21&2 B&2B Uniaxial &

Biaxial1%,2%&3%

Fig. 6 :ShearlayereffectforGB,RGBandPRGB(Shivashankaretal.1993)

7


WherePp’=Thepassivepressuredevelopedoneachoffoursidesofsquarecolumnofgranularsoilbeneaththesquarefooting.

B=Widthofthesquarefooting

3.2 Confinement Effect

The tensile stressmobilized in the reinforcementwillprovide a confinement effect to the soil beneath thefooting. The shear stress developedalong the failuresurfaceduetothisconfiningstress isconsideredhere(Fig.7).Theequationproposedforstripfootingwas

ΔBCRCE = 2τ2/Q ...(8)

τ2 = TRtanfs ...(9)

ΔqCE = 2τ2/B ...(10)

Where τ2=Totalverticalforcealongthepunchingshearfailure planedue to confinement effect ofreinforcement

TR=Tensilestressmobilizedinthereinforcement=2Lsvtand

L= Lengthofreinforcementbeyondthefailuresurface

sv=Verticalstressatthelevelofreinforcement

d= angleoffrictionbetweenreinforcementandsoil=fsforgeogrid

Theaboveequationwasdevelopedforastrip footing.Inthepresentstudy,sinceasquarefootingisused,theequationismodifiedasgivenbelow

τ2 =TR’tanfs ...(11)

ΔBCRCE = 4τ2/Q ...(12)

ΔqCE = 4τ2/B2 ...(13)

WhereTR’=Tensilestressmobilized in reinforcementbeyond each of the four sides of square column ofgranularsoilbeneaththesquarefooting

B=Widthofthesquarefooting

InthecaseofPRGB,ifthefrictiononreinforcement(ononesideofthesquareprism,alongplaneofreinforcement)islessthantheappliedprestress,valueofTR’istakenasequaltothevalueofappliedprestress.Ifthefrictioninreinforcementismorethanappliedprestress,thevalueofTR’istakenasequaltovalueoffrictionalresistanceoverthereinforcement.

3.3 additional Surcharge Effect

Theverticalstressesalongthepunchingshearfailuresurface due to shear layer effect and confinementeffectareenvisagedtoactasanadditionalsurchargestresson theunderlyingweaksoil.Therewill beanimprovementinbearingcapacityduetothissurchargestress. The distribution of this surcharge stresswas assumed to be exponential for a strip footing(Shivashankar et al. 1993), as shown in Fig 8. Theimprovementinbearingcapacityduetothissurchargestressisgivenby

qo=0.84(ΔqSL+ΔqCE) ...(14)

Whereqo= Intensity of surcharge stress at the edgeofthefailureplaneduetoshearlayerandconfinementeffects

Fig. 7:ConfinementeffectforGB,RGBandPRG(Shivashankaretal.1993)

Fig. 8 :SurchargeeffectforGBandRGB (Shivashankaretal.1993)

Surchargestresswasenvisagedtodecreaseexponen-tially from qo at edge of footing to 0.01qo at end ofreinforcement.Inthepresentstudy,incaseofPRGB,the additional surcharge stress is envisaged to beuniform over the reinforcement in the direction ofprestressing (Fig 9). This is also justified from themeasuredsettlements.IncaseofUniaxialprestressing,thesurchargestressisconsideredtobeuniforminthedirection of prestress and to decreaseexponentiallyin the cross direction. Average surcharge stress isconsideredaroundthesquarefootingandaccordinglyΔBCRSEisestimated.

ΔqSE = qavgxNq ...(15)

ΔBCRSE=ΔqSE/Q ...(16)




Fig. 9:SurchargeeffectforPRGBproposedin thepresentstudy

4. FiNiTE ElEmENT aNalySiS

In the present study, loading tests on ReinforcedGranularbedsarealsosimulatednumericallyusingtheprogramPLAXIS (version8)which is a finite elementsoftwarepackage.Duetosymmetryofthesoil-footing-reinforcementsystem,anaxisymmetricmodelisusedtocarryoutthefiniteelementanalysis.Thesettlementoftherigidfootingissimulatedusingnonzeroprescribeddisplacements.

Thesoilismodeledusing15nodedtriangularelements.Thereinforcementismodeledusingthe5-nodedgeogridelement.Theprestressisappliedasahorizontaltensileload to the reinforcement (Fig10).Mediummeshsizeisadoptedinallthesimulations.ThedescretizedmodelisalsoshowninFig10.Tosimulateexactlythetestingprocedureinthelaboratory,stagedconstructionprocedureis adopted in the calculationphase. In the first stage,weaksoiluptoitstoplevelissimulated.Inthesecondstage,sandup to thebottom levelof reinforcement issimulated. In the third stage the reinforcement withprestressissimulatedandinthefourthstagesandabovethe reinforcement is simulated. In the final stage thefootingwithprescribeddisplacementissimulated.Suchastagedconstructionprocedureisnecessarybecausethe reinforcement should be prestressedbefore fillingsoil above it, otherwise the friction between soil andreinforcementwillpreventtheelongationofreinforcementdue to prestressing. The deformed shape and stressdistributioninsoilareshowninFig11.

Fig. 11:DeformedshapeandStressdistributionafterloading

5. rESUlTS aNd diSCUSSiONS

5.1 improvement in Bearing Capacity

Vertical stress vs normalized settlement curves ofprestressed reinforcedgranularbedsoverlying (moist)weaksoil1,bothexperimentalandfromFEAareshowninFigs12to15.ThefootingsettlementSisexpressedinnondimensionalformasS/B(%).Itisclearlyobservedthattheadditionofprestresssignificantlyimprovedthesettlementbehaviourofsoil.Theloadcarryingcapacityoffootingisalsosignificantlyimproved.

From Fig 12 which represents the variation ofbearingpressurewithfootingsettlementofuniaxiallyprestressed granular bed of thickness Bwith singlelayer reinforcement overlying (moist) weak soil 1, itcanbeseenthatmaximumimprovementisobservedwhenthemagnitudeofprestressisequalto2%ofthetensilestrengthof reinforcement.Furtheradditionofprestressdidnotshowanyimprovementinsettlementbehaviour.HoweverforagranularbedofthicknessBwith biaxially prestressed single layer reinforcementoverlying (moist)weaksoil1, it isobserved that themaximumimprovementinsettlementbehaviouroccurswhenthemagnitudeofprestressisequalto1%ofthetensilestrengthofreinforcement.Furtherincreaseinprestressdidnotshowanyimprovementinsettlementbehaviour(Fig.13).

Theresultsobtainedfromagranularbedofthickness2Bwithuniaxiallyprestressedsinglelayerreinforcementoverlying(moist)weaksoil1areshowninFig.14.Itisobservedthatthemaximumimprovementiswhenthemagnitudeofprestress isequal to3%of the tensilestrengthofreinforcement.Theresultsobtainedfromagranularbedofthickness2Bwithbiaxiallyprestressedsinglelayerreinforcementoverlying(moist)weaksoil1indicatesthatmaximumimprovementisgotalsowhenthemagnitudeofprestressisequalto3%ofthetensilestrengthofreinforcement(Fig.15).

5.2 Bearing Capacity ratio

Theratioofbearingcapacityofimprovedsoiltothatoforiginalsoilistermedasbearingcapacityratio(BCR).TheFig. 10 :GeometricModelandDescretizedmodel

9


Fig. 13 :StressversusnormalizedsettlementcurvesforgranularbedofthicknessBwithBiaxiallyPrestressedsinglelayerreinforcementoverlying(moist)weaksoil1

Fig. 12 :StressversusnormalizedsettlementcurvesforgranularbedofthicknessBwithUniaxialyPrestressedsinglelayerreinforcementoverlying(moist)weaksoil1

Fig. 14:Stressversusnormalizedsettlementcurvesforgranularbedofthickness2BwithUniaxialyPrestressedsinglelayerreinforcementoverlying(moist)weaksoil1




BCRvaluesat5mmsettlement(S/B=5%)aredeterminedforvariouscasesfromthestressvsnormalizedsettlementcurves. The variations ofBCRwith themagnitude of

Fig. 16 :VariationofBCRwithprestressingranularbedsoverlying(moist)weaksoil1

Fig. 17 :VariationofBCRwithprestressingranularbedsoverlying(submerged)weaksoil2

prestressforvariouscasesareplottedinFig16andFig17,forweaksoil1andweaksoil2respectively.

Fig. 15 :Stressversusnormalizedsettlementcurvesforgranularbedofthickness2BwithBiaxiallyPrestressedsinglelayerreinforcementoverlying(moist)weaksoil1

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The experimental results obtained from granularbeds of thickness B and 2Bwith single and doublelayerreinforcementoverlying(moist)weaksoil1arepresentedinFig16.ItisobservedthatforgranularbedsofthicknessBwithuniaxiallyprestressedsinglelayerreinforcement,theBCRincreasestilltheprestressisincreasedto2%.AfurtherincreaseinprestressreducestheBCR.Incaseofbiaxialprestressing,1%prestressisgivingmaximumBCR.At2%and3%prestress,theBCRvaluesattainedduetouniaxialprestressingandbiaxialprestressingarenearlyequal.Ingranularbedsofthickness2B,theBCRincreaseswithprestressinbothuniaxialandbiaxialprestressing.Ingeneraltheimprovementattainedwithgranularbedsofthickness2BismorethanthatwithgranularbedsofthicknessB. However at 1% prestress, the BCR observed ingranularbedofthicknessBwithbiaxiallyprestressedsinglelayerreinforcementismorethanthatofgranularbedofthickness2Bwithuniaxiallyprestressedsinglelayer reinforcement. Ingranularbedsof thicknessBwith two layersof reinforcement, themaximumBCRisattainedataprestressof2%forbothuniaxialandbiaxialprestressing.Butforgranularbedsofthickness2B,maximumBCR is attained at a prestress of 3%and the improvementattainedwhen theprestress isincreasedfrom2%to3%isveryless.

In general double layer reinforcement gave moreimprovementthansinglelayerreinforcementandbiaxialprestressing gavemore improvement than uniaxialprestressing.Itisobservedthatat1%and2%prestress,granular bedof thicknessBwith biaxially prestresseddoublelayerreinforcementgivesmoreimprovementthangranularbedofthickness2Bwithuniaxiallyprestresseddouble layer reinforcement. It is also observed thatgranularbedofthickness2Bwithbiaxiallyprestressedsinglelayerreinforcementgivesmoreimprovementthangranularbedofthickness2Bwithuniaxiallyprestresseddoublelayerreinforcement.

Figure17presentstheexperimentalresultsobtainedfromgranularbedsoverlying (submerged)weaksoil2.IngeneraltheBCRvaluesattainedin(submerged)weaksoil2due toprestressing the reinforcement ismuchhigherthanthatattainedin(moist)weaksoil1.Ingranularbedsof thicknessBwithbothsingleanddoublelayerreinforcement,theimprovementattaineddue to uniaxial prestressing ismore than that withbiaxialprestressing.Thisiscontrarytothatof(moist)weaksoil1wherebiaxialprestressinggavemoreBCRthanuniaxialprestressing.Ingranularbedsofthickness2B,for(submerged)weaksoil2,biaxialprestressinggivesmoreBCRthanuniaxialprestressing,which issimilar to (moist)weaksoil 1. It isobserved that forgranularbedsofthickness2BtheBCRisreachingapeak value betweena prestress of 1%and2%andthenreducing.Thisiscontrarytothatof(moist)weaksoil1whereBCRincreasedwithprestress.

Duringexperimental investigationwithgranularbedsoverlying(submerged)weaksoil2,itwasobservedthatcapillarywaterrisesintothedrysandingranularbed,fromthesubmergedsoilbelow,duringthecourseofexperiment.IngranularbedsofthicknessB,thesandsurrounding the reinforcement becamemoist duringthe experiment. In granular beds of thickness 2B,theheightof reinforcement from thesubmergedsoilsurfaceismoreandthecapillarymoistureatthelevelofreinforcementisverylesscomparedtothatofgranularbeds of thickness B. The difference in behaviour ofgranularbedsoverlyingsubmergedsoilcouldbeduetothepresenceofthiscapillarymoistureinsand.

5.3 Settlement measurement at the interface after Test in Case of (moist) Weak Soil 1

Thedistributionofsettlementattheinterfacebetweensand and (moist) weak soil 1, in a granular bed ofthicknessB,withsinglelayerreinforcement,subjectedtouniaxialandbiaxialprestressingisgiveninFig18.

Fig. 18 :DistributionofsettlementattheinterfacebetweenRGBand(moist)weaksoil1whenthicknessofgranularbedisB



Ingeneralthesettlementoftheunderlyingweaksoilis lesser incaseofbiaxialprestressingthanuniaxialprestressing.Thesettlementofweaksoil isfoundtobeleastwhenthebiaxialprestressisequalto3%ofthetensilestrengthofreinforcement

Theinterfacesettlementalongthedirectionofprestressand along its perpendicular direction, during uniaxialprestressing of a granular bed of thickness B, withsingle layer reinforcement, is presented in Fig 19. Itis observed that along the direction of prestress, theinterfacesettlement,isdistributedonawiderareathaninthecrossdirection.

5.4 Numerical analysis

All the above various casesare analysednumericallyusingthe‘improvisedmodel’ofShivashankaretal.(1993)proposed in this paper. TheBearingCapacityRatios(BCRs)obtainedexperimentallyandthosepredictedbythemodelforsinglelayeranddoublelayerreinforcementsareshowngraphicallyinFig.20andFig21respectively.Itisobservedthatthemodelpredictsthebearingcapacityratiowithfairlygoodaccuracy.

Fig. 20:Comparisonbetweenobservedandpredictedvaluesofbearingcapacityratios(BCRs)forGB,RGBandPRGBwith single layer reinforcement overlying(moist) weak soil 1and (submerged) weak soil 2

Fig. 19 :DistributionofsettlementattheinterfacebetweenRGBand(moist)weaksoil1,inthedirectionofprestressandinitsperpendiculardirection,forgranularbedofthicknessB,whenprestressisUniaxial.

Fig. 21:Comparisonbetweenobservedandpredictedvaluesofbearingcapacityratios(BCRs)forGB,RGBandPRGBwithdoublelayerreinforcementoverlying(moist)weaksoil1and(submerged)weaksoil2

13


6. CONClUSiONS

Basedon the results obtained fromexperimental andnumericalstudies,thefollowingconclusionscanbemadeonthebehaviourofprestressedreinforcedgranularbedsoverlyingweaksoils.

1. Theadditionofprestress togeogrid reinforcementsignificantly improves the bearing capacity andsettlement behaviour of the soil. Prestressing thegeosynthetic reinforcement results in increasedloadbearingcapacityofsoilwithouttheoccurrenceoflargesettlements,ascomparedtogeosyntheticswithoutanyprestress.

2. Theimprovementinbearingcapacitydependsuponthethicknessofgranularbed,magnitudeofprestress,direction of prestress and number of layers ofreinforcement.Theimprovementinbearingcapacityis found to bemorewith biaxial prestressing thanuniaxial prestressing.The improvement in bearingcapacity increaseswith the thickness of granularbed.

3. TheresultsobtainedfromFiniteelementanalysesareinreasonablygoodagreementwiththeexperimentalresults.

4. Theproposednumericalmodelpredictsthebearingcapacityratiosforgranularbedsoverlyingweaksoilwithreasonablygoodaccuracy.

5. Predictionisbetterforweaksoil1thanforweaksoil2.

rEFErENCES

1. Alamshahi,S.andHataf,N.(2009).Bearingcapacityofstripfootingsonsandslopesreinforcedwithgeogridandgrid-anchor,Geotextiles andGeomembranes,27(2009)217–226.

2. Arun Kumar Bhat, K., Shivashankar, R. andYaji,R.K.(2008),“CasestudyoflandslideinNH13atKethikalnearMangalore,India”,6thInternational

Conference on Case histories in GeotechnicalEngineering,Arlington,VA,USA,paperno.2.69

3. Binquet,J.andLee,K.L.(1975).Bearingcapacitytests on reinforced earth slabs. Journal ofGeotechnicalEngineeringDivision,ASCE101(12),1241–1255.

4. Lovisa,J., Shukla,S.K. andSivakugan,N. (2010).Behaviour of prestressed geotextile-reinforcedsand bed supporting a loaded circular footing,GeotextilesandGeomembranes,28(2010)23–32.

5. Madhavilatha,G.andSomwanshi,A.(2009).Bearingcapacityofsquarefootingsongeosyntheticreinforcedsand,Geotextiles andGeomembranes, 27 (2009)281–294.

6. Sharma,R., Chen,Q., Farsakh,M.A. andYoon,S.(2009). Analyticalmodeling of geogrid reinforcedsoilfoundation,GeotextilesandGeomembranes,27(2009)63–72.

7. Shivashankar,R., Madhav, M.R. and Miura,N.(1993).Reinforcedgranularbedsoverlyingsoftclay,Proceedingsof11thSouthEastAsianGeotechnicalConference,Singapore,409–414.

8. Shivashankar, R. and Reddy, A.C.S. (1998).Reinforced granular bed on poor filled up shediground, Proceedings of the IndianGeotechnicalConference-1998,Vol.1,301-304.

9. Shivashankar, R. and Setty, K.R.N.S. (2000).“Foundation problems for ground level storagetanks in and aroundMangalore”, Proceedings ofIndianGeotechnicalConference2000,IITBombay,Mumbai.

10.Vinod, P., Bhaskar,A.B. andSreehari,S. (2009).Behaviourofasquaremodelfootingonloosesandreinforcedwith braided coir rope,Geotextiles andGeomembranes,27(2009)464–474.



1. iNTrOdUCTiON

The conventional theories of consolidation developedbyBarron (1948) andHansbo (1979) used often fortheanalysisofradialconsolidationofclaystreatedwithprefabricatedverticaldrains(PVDs)areapplicableonlyfornormallyconsolidatedsoils.However,mostsoftclaysare lightly overconsolidated because of cementation,glaciation,isostaticuplift,creep,excavations,erosions,groundwater level fluctuations, etc. Soft clays alsoexhibit pseudo-preconsolidation effect due to agingwithoverconsolidationratio(OCR)rangingbetween1.0and2.0.Fig.1(a)showsgeotechnicalprofileofRiodeJaneiroSarapuisoftlaywithOCRdecreasingfrom4at1.0mdepthto1.8at10mdepthbelowthegroundleveldue toagingandwater tablefluctuation (AlmeidaandMarques,2002).SimilarlyFig.1(b)depictsgeotechnicalprofileofBangkoksoftclaydepositwithOCRdecreasingfrom4.5at1.5mto1.2at8mdepthbelowthegroundlevel(Bergadoetal.2009).MadhavandMiura(1994)

reportedOCRvaluesrangingbetween1.0and4.0 forSaga plain, one of the lowlands in Japan. Therefore,under an applied load intensity, the soil initially goesthrough a reloading stage for effective stresses lessthan the pre-consolidation stress and passes on tothe virgin compression state at later times.Mesri andRokhsar (1974) presented a very general theory ofconsolidation considering preconsolidation effects,variationsofcompressibilityandpermeability,secondarycompressionandfinitestrains.Murakami(1980)studiedtheconsolidationofoverconsolidatedandsensitiveclays.Scott (1989) developed a theory of one-dimensionalconsolidationofOCclaysasaphasechangeprocessassuming that the clayexhibits no compressionup tothe preconsolidation stress.MadhavandMiura (1994&2004)presentedconsolidationtheoriesforlightlyOCClaysbasedonlinearandnon-lineartheoriesasphasechangeprocess,butapplicableonlyforonedimensionalconsolidation. Ayub Khan et al. (2011) presented a

CoNsoLIdAtIoN oF LIGhtLY oC CLAYs WIth PVds As A PhAse ChANGe ProCess

p. ayub khanDepartment of Civil Engineering, ACE Engineering College, Ankushapur, Ghatkesar, Andhra Pradesh, India

m. r. madhavVisiting Professor, IIT Hyderabad and Professor Emeritus, Department of Civil Engineering,

J.N.T.U.H., College of Engineering, Hyderabad, India

E. Saibaba reddy Department of Civil Engineering, J. N. T. U. H. College of Engineering, Hyderabad, India

aBSTraCT

Many natural clays are lightly overconsolidated with overconsolidation ratio ranging between 1.0 and 4.0 because of cementation, glaciation, isostatic uplift, creep, erosion, etc. Under an applied load, the soil passes initially through a reloading stage for effective stresses less than the pre-consolidation stress and then on to the virgin compression state at later times. The conventional theory of radial consolidation used often for the analysis of clays treated with PVDs is applicable only for normally consolidated soil. This paper presents a consolidation theory for radial flow in lightly overconsolidated clays as a phase-change process. The void ratio - effective stress relation is considered to be bilinear with mvo and mvn being the slopes for the recompression and virgin compression ranges respectively but with the respective coefficients of consolidation to be constant in each state. The governing equation of consolidation is solved numerically by the finite difference method and parametric study carried out. The variations of degree of dissipation of pore pressure and of degree of settlement with time factor are found to be different from each other unlike in the case of normally consolidated soils and very sensitive to the overconsolidation ratio of the soil. Lightly overconsolidated soils exhibit faster rates of pore pressure dissipation and degree of settlement compared to those for normally consolidated soils.

Keywords : Clay, Consolidation, Lightly overconsolidated, Overconsolidation ratio, Phase change, Pore pressure, Stress increment ratio.

14

15


Consolidation of Lightly OC Clays with PVDs as a Phase Change Process

theoryforradialconsolidationoflightlyOCsoilsbasedonnon-linear theory.Nosimple theory isavailable forradial consolidation of lightly overconsolidated soilstreatedwithPVDsbasedonlineartheory.Inthispaper,the conventional linear theory of consolidation forradial flow (Barron, 1948) is extended to cover lightlyoverconsolidatedclaysasaphasechangeprocess.

2. VErTiCal draiNS (pVds)

PreloadingwithPVDsisoneofthemostpopulargroundimprovementtechniquesusedworldwideforsoftclays.PVDsareusuallyinstalledinsquareortriangulararrays(Fig.2).ThePVDsshortenthedrainagepathbyreorientingtheflowinradialdirectionandtherebyacceleratetherateofconsolidationunderloading.Theequivalentdiameterofthedrain,dw,isequalto2(a+b)/pwhereaandbarerespectively thewidth and thicknessof thePVD.Theequivalentdiameteroftheinfluencezone,de,arrivedatbyequatingtheareasisde=1.13S&1.05Sforsquareandtriangularpatternsrespectively,whereS=spacingofdrains.PVDandthesurroundingsoiluptoaradiusofre(=de /2)constituteanaxisymmetricunitcellforanalysisofconsolidationwithradialflowunderload.

3. aNalySiS

A finite homogeneous lightly overconsolidated claylayerof thickness,H,subjected toastress increment,q, with PVDs (Fig. 3) is considered. The proposedtheory herein, considers all the assumptions (linearityof void ratio – effective stress relation, constantcoefficients of permeability and consolidation) of theconventionalBarron’stheoryexceptthatthesoilislightlyoverconsolidated.Thevoidratio-effectivestressrelationisconsideredtobebilinearwithmvoandmvnrepresentingtheslopesfortherecompressionandvirgincompressionrangesrespectively(Fig.4).Consequently,thetwostates,OCandNCof the consolidating soil aregovernedbytheir respective coefficients of consolidation,Cho andChn,inverselyproportionaltomvoandmvnandassumedconstantwitheffectivestressbutdifferentforeachstate.Fig.5showsdifferentcoefficientsofconsolidationeachconstant inOCandNC stateswith sharp change atthepreconsolidationpressure,fortypicalsoftclayinanoedometertest.

(a)SarapuiSoftClay(AlmeidaandMarques,2002) (b)BangkokSoftClay(Bergadoetal.,2009)Fig. 1:TypicalFieldOCRandotherCharacteristics

Fig. 2:(a)TriangularArrangementofPVDsand (b)FlowinUnitCell

Fig. 3:DefinitionSketch



Fig. 5:TypicalResultsforSoftClay(MadhavandMiura,2004)

During theconsolidationprocess,eachelementof thesoil followsthesamepathABC(Fig.4).But,pointsatdifferentradialdistancespassthroughtheinterfacepoint,B, at different times.Once consolidation commences,points close to the drainage boundary (PVD surface)traversethroughtheOCstate(AtoB)veryrapidlywiththerateofconsolidationgovernedbythecoefficientofconsolidation,Cho.As theeffectivestress (s’)exceedsthepreconsolidationstress(s’c),thesoilelementtransitstoNCstateandfollowsthepathBCconsolidatingwithacoefficientofconsolidation,ChnwhichismuchsmallerthanCho.TheinterfacebetweenNCandOCstates(Fig.3)moves away from the drainage boundary towardsthe impervious boundary (the outer boundary of theunit cell) as a function of time during consolidation.Thus, theconsolidationof lightlyOCsoilssimulatesamovingboundaryproblem.Afteracertaintimethewholeconsolidatingsoilfollowsthevirgincompressionline(NCphase).ThetimeafterwhichalltheelementsofsoilareinaNCstatedependsuponthestressincrement,q andtheoverconsolidation ratio,OCR=s’c/s’o,wheres’c isthepreconsolidationstressands’o-theinitialeffectivestress.

Atanytime,t,theinterfacebetweenNCandOCisataradius,rin,fromthedrainageboundary(Fig.3)andtheconsolidationphenomenon ineachregion isgovernedbythefollowingequations:

...(1)

...(2)

where u=excessporepressureataradialdistance,r andtime,t.

The initial andboundary conditions for the radial flowconsolidationare:

Att = 0,u = q for rw ≤ r ≤ re; ...(3)

Fort>0,u = 0at r = rw and∂u/∂r = 0atr=re....(4)

The conditionsat the interface, rin(t), betweenNCandOCphasesarederivedtreatingthesoilasatwolayeredone.Continuityofporepressuresand rateofflowaresatisfiedas

for ...(5)

Theporepressureandtherateofflowarecontinuousacross the interfacebut not the compressibilities. It isdifficult toobtainanalyticalsolutiontoEqs.(1)and(2)subjecttotheconditionsspecifiedinEqs.(3)through(5).Hencethefinitedifferenceapproachisadoptedtosolvetheaboveequationsbydiscretizingtheunitcellradiallyintomelementsofequalthickness,Δr[=(re - rw)/m].Eqs.(1)and(2)innon-dimensionalformare

...(6)

wherei=anodeinthefinitedifferencediscretizedunitcellataradius,r

W = u/q; R = r/de; ΔR = Δr/de,

T = Chn.t/de2; ...(7)

forr < rin(t)(NCphase), ...(8)

forr > rin(t) (OCphase),...(9)

Rc = Cho / Chn = 1/μ; μ = mvo / mvn.

Attheinterface,i.e.r = rin,βcanbeshown(Das,1983)as

β = Rc.βNC / fin with fin = (1+Rc)/2 ...(10)

Thenormalizedaverageresidualporepressure,Wav,isdefinedas

...(11)

Fig. 4:Bi-lineare-s’Relation

17



whereUav(T) istheaverageresidualporepressureanduo,theinitialexcessporepressure(=q).

SettlementofanelementS(r, t) atadistance,ris:

Fora’<a’c(OCphase);S(r.t) = mvo (a’– a’c) or...(12)

= μ mvn q(1–W)H ...(13)

Fora’>a’c(NCphase);

S(r.t) = mvo (a’– a’c)H + mvn (a’– a’c)Hor ...(14)

...(15)

Theaveragesettlementofthesoil(unitcell),

...(16)

Thefinalsettlementofthesoil,

Sf = mvo (a’c– a’o)H + mvn (a’f– a’c)H or ...(17)

...(18)

Thedegreeofsettlement,Usisdefinedas,

...(19)

whereSIR=q/s’o-thestressincrementratioandOCR=s’c/s’o-theoverconsolidationratio.

4. rESUlTS aNd diSCUSSiON

Numericalanalysisiscarriedoutbyvaryingthenumberof elements,m, into which the consolidating soil isdividedradiallyofequalthickness.Comparisonofresultsindicatednoimprovementintheaccuracyoftheresultsfor the number of elements,m, beyond40.However,in thepresentanalysis, thenumberofelements,m, ischosenas100forimprovedaccuracy.ThevalueofβOC ischosenas0.15tokeepnumericalerrorsinthefinitedifferenceequationstoanegligiblelevel.Thevalueofn (= re/rw)isconsideredas15,asusedcommonlyinthefield.Parametricstudyiscarriedoutforthefollowingrangesfortheparameters:

OCR=1to4;SIR=1to10;μ=0.05to0.70.

5. pOrE prESSUrE diSSipaTiON

Thevariationofnormalizedaverageresidualexcessporepressure,Wav,withtimefactor,T,fordifferentvaluesofOCRisshowninFig.6fornof15,SIRof1.0andμof0.20.OCRof1correspondstoNCstateandthevariationoftheaverageresidualporepressurewithtimeagreeswiththeresultsofBarron’stheory(1948).Thedegreeofdissipationofexcessporewaterpressurewith time isfasterwithincreasingvaluesofOCRasthecoefficient

Fig. 6:Wavvs.T-EffectofOCR

The variation of the normalized average excess porepressure,Wav,withtimefactor,T,isalsoinfluencedbystressincrementratio(Fig.7)forOCsoilsunlikeinthecaseofNCsoils.ForNCsoilfollowinglinearvoidratio-effective stress relation, the results are independentofSIR.However, if thesoilfollowslinearvoidratio-logeffective stress relation, SIR affects significantly theconsolidationphenomenonasobservedbothintheonedimensionalconsolidation(DavisandRaymond,1965)andradialconsolidation(AyubKhanetal.,2011).Asimilareffect canbeobserveddue toSIR if thesoil is lightlyOC.AtSIR(=1),thebehaviorisdominatedbytheOCphaseresultinginrelativelyfasterrateofdissipationofporepressures.WithincreasingvaluesofSIR,therateofconsolidationslowsdownandthebehaviorapproachestothatofaNCsoil(Barron’stheory)becauseathigherSIR,theconsolidationprocessismainlyinfluencedbytheNCphase.ForSIRincreasingfrom1to10,T50increasesfrom0.038to0.157.

ofconsolidationfortheOCphase,Chois5timesChn,thevaluefortheNCphase.ForOCRincreasingfrom1to1.25andto2,T50decreasesfrom0.168to0.108andto0.033respectively.ThekinksinthecurvesindicatethetransitionofthesoilfromtheOCphasetotheNCphase.PhasetransitionisnotobservedforOCRof≥2forSIRof1sincetheentirestressrangeiswithintheOCphaseonlythroughouttheconsolidationprocess.Fortimesbeyondthekinks,theaverageporepressureversustimecurvesshowrelativelyslowerdissipationofporepressuresduetoconsolidation in theNCphase.Thedissipation ratein the fullyNC phase appears to have slowed downwiththeincreaseinOCRvaluesasthesoilhasalreadyconsolidatedsignificantlyintheOCphase.



Fig. 7:Wavvs.T-EffectofSIR

Theeffectofμ,theratioofcoefficientsofvolumechangeforrecompressiontothatforvirgincompressiononthedissipationofporepressuresisdepictedinFig.8.LikeinthecasesofOCRandSIR,theratioμ alsoexhibitspronouncedeffect on thedissipationof porepressurewithtimeinlightlyOCsoils.SmallvaluesofμimplylargevaluesofcoefficientsofconsolidationintheOCphaseandhencethedissipationofporepressurewithtimeisfaster.TheporepressuredissipationisfasterintheearlystagesandbecomesslowerinthelatterstagesbecauseofthechangeofthephaseofthesoilfromOCtoNC.Asexpected,thecurvestendtoapproachthatofBarron’stheory for increasedμ values. In the later stages thecurvestendtomergeindicatingthetransferofsoilintofullynormallyconsolidated.

Fig. 9:VariationofWwithDistance-EffectofOCR

6. dEGrEE OF SETTlEmENT

The curves of degree of settlement,Us, versus timefactor,T,exhibitsimilartrendsinthatUsoccursfasterforhighervaluesofOCR(Fig.10).OCRof1isanalogoustoNCsoilandthecurveisidenticaltotheonegivenbyBarron(1948).Thus,comparedtoaNCsoil,alightlyOCsoilexhibitsfasterratesofconsolidationintheearlyandintermediate stages of consolidation.With increasingOCRfrom1to1.5andto2,T50decreasesfrom0.168to0.156andto0.033.

Thestress incrementratio,SIRhas insignificanteffectonthevariationofdegreeofsettlementwithtimefactor(Fig.11).However,forSIRof1,therateofsettlementis slightly fasterbutonly in the intermediatestagesofconsolidationsincetheconsolidationprocessisgovernedbybothOCandNCphases.AthigherSIR,thebehaviorismainlycontrolledbyNCphaseandasaresultthecurvesbecomeclosertothatofBarron’stheory.Thedegreeofsettlement,Us,versustimefactor,T,relation isalmostindependentof the ratioμ (Fig.12)andnearly followsBarron’stheoryforallvaluesofμ.Fig. 8:Wavvs.T-Effectofμ

The variations of normalized residual pore pressure, W (=u/q)withradialdistancearecomparedinFig.9forOCRof1(NCsoil)and1.5(LightlyOCsoil).Atanygivenradialdistance, the residualporepressure is relativelysmallerorthedegreeofdissipationofporepressureisrelativelylargerforlightlyOCsoilcomparedtothoseforNCsoilasdiscussedearlierinthecaseoftheeffectofOCRontheaverageresidualexcessporepressure,Wav.TheeffectofoverconsolidationissignificantintheouterreachesoftheunitcellcomparedtothepointsnearertothePVD.

19



Fig. 11 :Usvs.T-EffectofSIR

TheaboveobservationsmadeforlightlyOCsoilsintermsofthevariationsofdegreeofsettlementandofdissipationofporepressuresforradialconsolidationaresupportedbythefindingsforone-dimensionalconsolidationoflightlyOCsoilsbyMesriandRokhsar(1974),Tavenasetal.(1979)andMadhavandMiura(1994).

7. EFFECT OF phaSE TraNSiTiON ON US aNd Up

ForNCsoils if void ratio – effective stress relation isconsidered to be linear, the degree of settlement,Usand degree of dissipation of average pore pressure,Up (=(1-Uav)100) are identical. However, in the caseof lightlyOCsoils undergoing phase transition duringconsolidation,thevariationsofUsandUpwithtimearenotidentical(Fig.13).Thedegreeofsettlementatanytimeisrelatively lessthanthedegreeofdissipationofporepressure.ThiseffectmanifestsbecausetheinnerareawhichisclosertothePVDandintheNCstateisrelativelysmallerinmagnitudecomparedtothelargeouterareawhichisintheOCstate.ThesettlementfortheOCstatedependsonmvo,thecoefficientofvolumechangewhichis relativelysmaller thanmvn, thecoefficientofvolumechangeforNCstate.WhileUpisabout78%,Usisonlyabout46%atatimefactorof0.1forOCRof1.75.

Fig. 10:Usvs.T-EffectofOCR

Fig. 12:Usvs.T-Effectofμ

Fig. 13:ComparisonofVariationsofDegreesofSettlementandPorePressureDissipationwithTimeFactor

8. iNTErFaCE BETWEEN OC aNd NC phaSES

As the consolidation progresses, the effective stressincreasesandtheinterfacebetweenNCandOCstatesmovesawayfromthedrainageboundary(PVDsurface)towardstheimperviousboundary(outerperipheryoftheunitcell).TheshiftingofinterfacewithtimeisdepictedinFigs.14through16,showingtheeffectsoftheratiosOCR,SIRandμ.NearthePVD,beingclosetothedrainageface, thechangeofphasefromOCtoNCisrelativelyveryquickcomparedtotheareaawayfromthePVD.Asexpected,thetimefortheentiresoiltoshiftfromOCtoNC



phaseorthetimefortheinterfacetomovefromthePVDtotheboundaryofunitcellincreaseswiththeincreaseinOCR(Fig.14).ThetimefactorforchangeofphasefromOCtoNCincreasesfrom0.019to0.13withincreaseofOCRfrom1.1to1.9.ThetimefortheinterfacetomovefromthePVDtotheboundaryofunitcelldecreases(Fig.15)withincreaseinSIR,sinceathigherSIRvalues,theportionofOCphaseisrelativelyless.ThetimefactorfortheinterfacetomovefromthePVDtotheboundaryofunitcell,decreasesfrom0.048to0.016i.e.,by2/3forSIRincreasingfrom1to8.Fig16indicatesthatthetimefactorfortheinterfacetomovefromthePVDtotheboundaryofunitcelldecreaseswiththedecreaseinμsincesmallerμindicateshighercoefficientofconsolidationintheOCphasewhichcausesrapiddissipationofporepressure.TimefactorfortheinterfacetomovefromthePVDtotheboundaryofunitcelldecreasesfrom0.143to0.017forμ decreasingfrom0.7to0.05. Fig. 16:MovementofNC/OCInterfacewithTime–

Effectofμ

9. iNFlUENCE OF OCr ON T90

TheinfluenceofOCRonT90,thetimefactortoreach90%degreeofsettlement, isdepictedinFig.17fordifferentvaluesofSIR.ForSIR=1andOCRofup to1.85, theT90 isabout0.57andclose to thatofBarron’s theory.T90decreasessharplywithfurtherincreaseinOCRduetodominanceoftheeffectofOCphase.ForSIR=1andOCR=2, theT90 reduces to 0.1, i.e., about 1/5 of thevalueforOCR=1,andforOCR=2.2,T90reducesto0.005i.e.about1/115ofthevalueforOCR=1.SimilartrendscanbeobservedforothervaluesofSIRinthattheT90remainsclosetothatofNCsoiluptocertainOCRandbeyond thatvalueonly theT90decreasesverysharplywithincreasingOCR.Forexample,forSIRof1,2and3thevaluesofT90 inthecaseof lightlyOCsoils(withn=15andμ =0.2)agreewellwiththatforNCsoiluptoanOCRofabout1.85,2.8and3.8respectively.For

Fig. 17:InfluenceofOCRonT90

Fig. 14:MovementofNC/OCInterfacewithTime– EffectofOCR

Fig. 15 :MovementofNC/OCInterfacewithTime– EffectofSIR

21


OCRsmorethanthesevaluesT90decreasessharplywithincreasingOCR.ThusT90inthecaseoflightlyOCsoilsisclosetothatofNCsoiluptocertainOCRdependingupontheSIR,nandμvaluesbutdecreasessignificantlyforhigherOCRvalues.

10. SUmmary aNd CONClUSiONS

Lightly overconsolidated soils under a given stressincrement, initially undergo recompression for theeffectivestresslessthanthepreconsolidationpressureandpasson to thenormal compression state at latertimes.LightlyoverconsolidatedclaystreatedwithPVDsandsubjectedtopreloading,exhibitNCstatenearthePVDandOCstateawayfromthePVDwiththeinterfacebetweenthetwomovingawayfromthePVDasafunctionoftimeduringtheconsolidationprocess.Barron’stheoryis extended herein to analyse consolidation of lightlyoverconsolidated clays treatedwithPVDsasa phasechangeprocess.ThevariationsofdegreesofdissipationofporepressureandsettlementwithtimeforlinearradialconsolidationtheoryareshowntobedependentonOCRoflightlyoverconsolidatedclays.Lightlyoverconsolidatedsoilsexhibitfasterratesofporepressuredissipationanddegree of settlement compared to those for normallyconsolidatedsoils.Thevariationsofdegreesofdissipationofporepressureandsettlementwithtimearenotidenticalfor lightly overconsolidated clays in contrast to that inNCsoilsbasedonlineartheoryofconsolidation.WhilethedegreeofdissipationofporepressureversustimeissignificantlyaffectedbytheSIRandμ,thedegreeofsettlementversustimeisalmostindependentofbothSIRandμ.TherateofshiftingoftheinterfacebetweenOCandNCphasesisinfluencedbyOCR,SIRandμ.Thetimefactorfor90%degreeofsettlement(T90)inthecaseoflightlyOCsoilsisclosetothatforNCsoiluptocertainOCRdependinguponSIR,nandμvaluesbutdecreasessharplyforhigherOCRvalues.

rEFErENCES

1. AlmeidaM.S.S., andMarquesM.E.S. 2002 Thebehavior of Sarapui soft clay. Proc. Internationalworkshopon characterizationandEng. propertiesofnaturalsoils,Singapore.vol.1:477-504.

2. AyubKhanP.,Madhav,M.R.,andReddyE.S.2010Effectofnon-linearconsolidationforradialflowon

porepressuredissipation.IndianGeotech.Journal.40(1):47-54.

3. AyubKhanP.,Madhav,M.R.,andReddyE.S.2011Radialconsolidationoflightlyoverconsolidatedclays.Proc.ofIndianGeotechnicalConference,Dec15-17,Kochi:871-874.

4. BarronR.A.1948Consolidationoffinegrainedsoilsbydrainwells.Trans.ASCE.113(2346):718–754.

5. Bergado D.T., Phienwej, N., Jamsawang, P.,Ramana,G.V., Lin,S.S., and Abuel-Naga H.M.2009Settlement characteristics of full scale testembankment on softBangkok clay improvedwithThermo-PVD and stiffened deep cementmixingpiles. Proc. of the 17th InternationalConferenceonSoilMechanics andGeotechnicalEngineering,Alexandria.Vol.3:1969-1972.

6. Das B.M. 1983, Advanced Soil Mechanics.HemispherePublishingCorporation:253-331.

7. DavisE.H.,andRaymondG.P.1965Anon–lineartheory of consolidation.Geotechnique. 15: 161 –173.

8. HansboS.1979Consolidationofclaybybandshapedprefabricateddrains.GroundEngineering.12(5):16-25.

9. MadhavM.R.,andMiuraN.1994OnedimensionalconsolidationoflightlyOCClays.IndianGeotech.Journal.24(1):34–49.

10.MadhavM.R.,andMiuraN.2004PhaseTransitioneffect on pre consolidation stress of soils. IndianGeotech.Journal.34(1):80–95.

11.MesriG.,andRokhsarA.1974Theoryofconsolidationfor clays. JGeotech,Engrg.,ASCE.100(.8):889-904.

12.Murakami Y. 1980 Amethod for estimating theconsolidationofnormallyconsolidatedClayofsomeage.SoilsandFoundations.20(4):83-93.

13.ScottR.F.1989Consolidationofsensitiveclayasaphasechangeprocess.JGeotech,Engrg.,ASCE.115(10):1439-1458.

14.TavenasF.A.,Brucy,M.,Magnan,J.P.,Larochelle,P.,andRoyM.1979AnalyseCritiqueodelaTheoriedeConsolidationUnidimensionelledeTerzaghi.Rev.FrancaisedeGeotech.,No.7:29-43.


Volume 2 v No. 2 v July 2013 22

1. iNTrOdUCTiON

Conventional brick bats are used in construction ofsubbase of flexible pavements. Due to large scaleincrease of construction of roads, particularly in ruralroadsinthirdworldcountries,amountofbricksneededtomeet the demand generated for brick bats, is ofenormousquantity.Productionofbricksneedssoilsofspecialqualitywhicharegenerallybeingprocuredmostlyfromagricultural lands.Such land isof limitedamountinpopulatedcountriestobesparedbecauseoflowpercapitalandholding.Furtheruseofagricultural landfor

brickmaking invariably invites sociological problems.Againforburningbricks,largeenergyisconsumed,while,conservationofenergyisofhighestpriorityintheworld.Inviewofthis,thereisgreatdemandofsearchingsomealternatesuitablematerialswhichmayreplacebrickbatsincaseofconstructionofsubbase.

Sandisbeingadvocatedasonealternativematerialwhichcouldbeusedinconstructionofsubbase.Inmanycasesofruralroad,sandisbeingusedextensivelyasagooddrainagelayerbutitalsobeingthoughtforidealsubbasematerialifitcouldbecapableofgeneratingcomparable

ImProVemeNt oF ChArACterIstICs oF sANd mIXING WIth NAtUrAL CoIr FIBer

Joyanta maity Bikash Chandra ChattopadhyayDepartment of Civil Engineering, Meghnad Saha Institute of Technology, Kolkata, India

Siba priyo mukherjeeDepartment of Civil Engineering, Jadavpur University, Kolkata, India

aBSTraCT

For expansion of land transportation system in India large number of road constructions is being made through different Government schemes. Such constructions require massive quantity of good brickbats for construction of subbase as per conventional method. Farming lands, which contribute soil for brick manufacturing is becoming scarce in India because of low per capita land holding and also use of agricultural lands encourages sociological problems in the neighbourhood. Further for burning brick large energy is consumed while in India conservation of energy is of highest priority. In view of this Government of India is emphasizing on use of alternate material to replace brickbats for construction of subbase.

Also, use of natural fiber materials, from coir, jute, etc. as reinforcing materials in soil is well-known for a long time for their use as soil reinforcement (additive material) and they are largely used in many countries like India, Ceylon, Philippines, etc. The main advantage of these materials lies in the fact that they are very cheap, eco-friendly and are also easily available in abundance in many countries. They can be used as additive material in the sub base course employing sand to have increased strength and decreased deformability.

Due to high permeability, sand is conventionally being used as mineral filter in layer along with conventional subbase. Due to restriction of use of brick bats in making subbase, search for alternative material for brick bats in construction of subbase is going on. Possibility of using solely reinforced sand in place of conventional subbase is worthwhile because natural fibers and sand are available in many locations.

In view of above, a systematic experimental program was undertaken with different sand coir fiber composites to be used in such cases. Standard Proctor tests were carried out on mixing natural coir fiber in various proportions and various lengths with three different types of sand i.e. fine brown sand, medium brown sand, and fine whitish gray sand to find optimum moisture content (OMC) and maximum dry density (MDD) of each case. California Bearing Ratio (CBR) tests were conducted at optimum moisture content of each case. The results indicate that CBR value is maximum for 5mm Coir fiber length for all types of sand. It is observed that Optimum percentage of fiber inclusion is 1.5% of the dry weight of sand for fine brown sand, and fine whitish gray sand while for medium brown sand optimum percentage of fiber inclusion is 1.0% of the dry weight of sand, beyond which the CBR value starts to decrease.

Keywords : Natural fibers, Eco-friendly, California Bearing Ratio.

23


CBRasrequiredforsubbase layer.SinghandPrasad(2004)hadshownthatGangaandChopansandscouldbeconvenientlyusedasmaterialforsubbase.Itisreportedthattheuseofthesesandswouldbeeconomicalforroadconstruction.

Reinforcingsoilwith randomlydistributedfiber canbeadvantageously employed as a ground improvementtechniqueinthecaseofembankments,subgradesandinsimilarotherproblems.Themainadvantagesofrandomlydistributedfibersarethesimplicityinmixing,maintenanceofstrengthisotropyandabsenceofpossibleplanesofweaknesswhichmaydevelop parallel to the orientedreinforcement.

Inclusionofrandomlydistributeddifferenttypesoffibermaterialswithsoilsarebeingstudiedelsewhere,suchas glass fiber (Pazare et.al 2002), Nylon fiber (Jainet al, 2003), synthetic fiber like polypropylene fibers(Consoliet.al,1998),Polyesterfiber(Kanirajet.al,2001),fragmentedrubbershreddedtyre(Lindh&Mattsson2004)etc.Butinmanycountries,thesyntheticfibersaremuchcostlierthannaturalfibers,whichaffectcosteffectiveness.Tomakeitcost-effective,locallyavailablenaturalfiberslikecoir,juteetc.couldbeusedasreinforcingmaterialwithsoilforlowtrafficunpavedroadsorroadswhichwillberemodeledperiodically.

AllcoastalcountriesincludingIndiaarewellendowedwithnaturalfibreslikecoirfiber.Coirfiberisabiodegradableorganicmaterialcontaining40%ligninand54%cellulose(RaoandBalan2000).Becauseof itshighcontentoflignin, coir is useful in improving the performance ofembankments. In case of typical embankment soils,whenmixedwith fibers, improvement in strength andstiffnessproperties,isveryusefulinshort-termstabilityand deformation requirements. Inclusion of randomlydistributed synthetic fibres in compacted fine grainedsoilshasbeenreportedtocausegenerationofgreaterstrengthandtoughness(Freitag,1986).Variousfailuremechanismsoffibre-reinforcedsoilshavebeenproposedbyMichalowskietal.1996andGopalRanjanetal,1996.

Even in sand, fiber stabilization technique has beenintroducedforairfieldandroadconstruction.Laboratoryand field studies to quantify the effects of numerousvariables on the performance of fiber stabilized sandlayerswhere sandwasmixedwith fibres randomly,hadshownimprovementinloadcarryingcapacity,andimprovementwasdependentonmaterialoffiber,aspectratio of the fiber included etc. (Santoni andWebster,2001,Santonietal2001).RaoandBalan(2000)afterconductingdrained triaxial test on specimensof sandreinforcedwithcoirfibres(25mmand50mm)upto1%,reportedasignificantgain in strengthparametersandstiffness.

2. OBJECTiVES

Inthepresentinvestigation,efficacyofusingnaturalcoirfiberwithlocallyavailablesandhasbeeninvestigated.AseriesofStandardProctortestandCBRtestaredonewithvarious lengthandproportionofnatural coir fibermixedwithlocallyavailabledifferenttypesofsandtofindtheircompactioncharacteristicsandstrengthproperties.Theresultsoftheexperimentalstudyareusedtostudytheimprovementofcompactionandstrengthpropertiesofcoir-sandcompositeswiththeaimofidentifyingthepercentagesbydryweightofsandandlengthofthecoirfiberscausingoptimum improvisation foreachcaseofsandused.

3. maTErialS aNd TEST prOGrammE

3.1 Sands

LocallyavailableFinebrownsand,Mediumbrownsand,andFinewhitishgraysandwereusedinthisexperimentalstudy. The reason for choice of these types of sandwasprimarilyfortheireasyavailabilityinmanypartsofthe country for possible use in practice. ThephysicalpropertiesofsandsusedaretabulatedinTable1andthegrainsizedistributioncurvesforthethreesandsusedintheexperimentsareshowninFig.1.

Table 1 :SummaryofPhysicalPropertiesofSands

properties Fine brown Sand medium brown Sand Fine whitish gray sandColour Brown Brown Whitishgray

Classification(IS) SP SP SM

Specificgravity(G) 2.63 2.65 2.54

D10,D30,D60inmm 0.16,0.23,0.33 0.29,0.51,0.62 0.1,0.17,0.22

Coefficientofuniformity,Cu 2.06 2.14 2.20

Maximumdrydensity(gm/cc) 1.62 1.63 1.59

Optimummoisturecontent(%) 15.3 14.5 15.5

Angleofinternalfriction(f) 38.8° 41.7° 37.2°

Californiabearingratio(%) 8.4 9.1 7.2

Improvement of Characteristics of Sand Mixing with Natural Coir Fiber



Fig. 1 :Grainsizedistributioncurvefordifferenttypesofsand

4. COir FiBErS

NaturalCoir fiberswere processed in the laboratorypurchasingripecoconutfromlocalmarket.Thefiberswerethenseparated from thecoconutshelland thendried insunforseveraldays(Fig.2).AfterthattheCoirfiberswerecleanedandcutintosmallpiecesoflength5mm,10mmand20mmforuseasfibermaterial.Fiberswererandomlymixedindifferenttypesofsandtoformhomogeneousmixture.ThesummaryofthephysicalpropertiesofcoirfibersusedintheexperimentsaregiveninTable2.

sandwasdonemanuallywithpropercareforpreparinghomogeneousmixtureateachstageofmixing. Itwasfound that the fibers could bemixedwith sandmoreeffectivelyinthemoiststatethaninthedrystate.

Table 3 :DetailsofSandFiberMix

Type of Sand used

length of Coir Fiber

Coir Fiber Content (with respect to weight of dry sand)

FinebrownSand

20mm 0.5%,1.0%,1.5%&2.0%

10mm 0.5%,1.0%,1.5%&2.0%

5mm 0.5%,1.0%,1.5%&2.0%

MediumbrownSand

20mm 0.5%,1.0%,1.5%&2.0%

10mm 0.5%,1.0%,1.5%&2.0%

5mm 0.5%,1.0%,1.5%&2.0%

Finewhitishgraysand

20mm 0.5%,1.0%,1.5%&2.0%

10mm 0.5%,1.0%,1.5%&2.0%

5mm 0.5%,1.0%,1.5%&2.0%

5. rESUlTS aNd diSCUSSiONS

FromStandardProctortests,theOMCandcorrespondingMDD for eachmix (asmentioned in Table 3) weredetermined.ForeachcaseunsoakedCBR testswereconductedatOMC.TheresultsofthesetestsaregiveninTable4.Theeffectofaddingcoir fibers,of varyingproportion and sizesas given inTable 3, ondifferentcompaction characteristics of the composites arediscussedbelow.(A)EffectofFibers inclusiononStandardProctor testresults:ThevalueofMDDandOMCobtainedfromthelaboratorytests are given in Table 4 for all the three types ofsands.(I)EffectofFiberContentonMDDforDifferenttypesofsandThevariationinMDDwithFibercontentareplottedfordifferenttypesofsandmixedwithvariouspercentageofnaturalcoirfiberofvaryinglengthareshowninFig.3.

Fig. 2:CoirFiberafterseparatedfromcoconutshell

Table 2 :SummaryofPhysicalProperties ofCoirFibers

property Coir fiberAv.Density(g/cc) 1.40Diameter(mm) 0.1-0.45

Toinvestigatetheeffectofinclusionofthesenaturalfibersofvariouslengthsandproportion,indifferentsandstaken,aseriesofStandardProctortestsandCBRtestshavebeenconductedasperI.S.codalprovision[IS2720,Part7(1980)andPart16(1987)].

Thevariouscombinationsofsand-fibermixturesusedinthetestsaregiveninTable3.Themixingofcoirfibersand

Fig. 3:EffectofcoirfibercontentonMDDfordifferenttypesofsand

25


The results show that as the fiber content increases,theMDDdecreasesforallthethreetypesofsand.ThedecreaseofMDDwithmixing increasinglycoirfiber isaccompanieddueto the lowerunitweightof thefiber,beingmixed.

(II)EffectofFiberContentonOMCforDifferent typesofsand

ThevariationinOMCwithFibercontentareplottedfordifferenttypesofsandmixedwithvariouspercentageofnaturalcoirfiberofvaryinglengthareshowninFig.4.Theresultsshowthatasthefibercontentincreases,theOMC increases forall the three typesof sand.FiberssoakwaterandthisyieldsanincreaseinOMCwithfibercontent.

(III)Effect ofFiber Length (coir) onMDD forDifferenttypesofsand

Thevariation inMDDwithFiber lengthareplotted fordifferenttypesofsandforvariouslengthofnaturalcoirfiber of varying percentage are shown in Fig. 5. Theresults show that as the fiber length increases, themaximumdrydensitydecreasesforallthethreetypesofsand.Thedecreaseindensityismostlikelyaresultofthefiberhavinglessspecificweightincomparisonwiththesandgrains.

Table 4 :SummaryofResultsofStandardProctorandUnsoakedCBRtests

Fiber length % of Fiber Fine brown sand medium brown sand Fine whitish gray sand

mdd OmC CBr mdd OmC CBr mdd OmC CBr 0.0% 1.613 15.2 8.4 1.625 14.5 9.1 1.588 15.6 7.2Coirfiber0.5cm 0.5% 1.598 15.4 10.6 1.623 14.7 10.1 1.584 15.8 10.9

1.0% 1.589 15.5 12.1 1.62 14.9 10.6 1.581 15.9 12.11.5% 1.578 15.7 12.6 1.615 15.2 9.8 1.576 16.2 12.52.0% 1.566 16 11.1 1.609 15.4 9.2 1.567 16.4 10.6

Coirfiber1.0cm 0.5% 1.588 15.4 10.1 1.62 14.9 9.8 1.58 15.9 9.71.0% 1.582 15.6 11 1.616 15.2 10.4 1.578 16.1 10.21.5% 1.568 15.9 11.6 1.608 15.5 9.9 1.568 16.5 10.32.0% 1.558 16.3 10.6 1.602 15.8 8.8 1.562 16.7 9.3

Coirfiber2cm 0.5% 1.58 15.6 9.7 1.615 14.9 9.5 1.578 16 8.91.0% 1.571 16 10.6 1.606 15.4 10 1.572 16.2 101.5% 1.564 16.2 11.2 1.598 15.7 9.5 1.564 16.6 10.22.0% 1.555 16.5 10.2 1.59 15.9 8.6 1.558 16.9 9

Fig. 4 :EffectofcoirfibercontentonOMCfordifferenttypesofsand

Fig. 5 :EffectofcoirfiberlengthonMDDfordifferenttypesofsand

(IV)EffectofFiberLength(Coir)onOMCforDifferenttypesofsand

ThevariationofOMCwithFiber lengthareplotted fordifferenttypesofsandmixedwithvariouslengthofcoirfiberof varyingpercentageareshown inFig.6.Fromthese figures it is observed that as the fiber length




Fig. 6 :EffectofcoirfiberlengthonOMCfordifferenttypesofsand

(B)EffectofFibersonCBRValue:

CBRvaluesobtainedfromlaboratorytestsaregiveninTable4.Theeffectsofvaryingfibercontentsandfiberlengthsof coir fiberson theCBRvaluesof themixedcompositeforthesandsusedintheinvestigationatOMCarediscussedbelow.

(i) EffectofFiberContentonCBRforDifferenttypesofsand

TheCBRvscoirfibercontentcurvefordifferenttypesofsandmixedwithvariouspercentageofnaturalcoirfiberofvaryinglengthsareshowninFig.7.FromtheCBRtestresults,itisobservedthattheCBRvaluesincreasewithincrease infibercontent (%)up toacertainmaximumlimitineachcaseandbeyondthelimititdecreasesforalltypesofsand.CBRvalueismaximumfor1.0%offibercontentforallthethreetypesofsand.Thelimitmaybetakenasoptimumfibercontent.Thefibercontent,whenincreasedbeyondtheoptimum,experienceslesscontactbetweenfiberandsand.ProbablythisisattributedtothereductionofCBR.

(ii)EffectofFiberLengthonCBRforDifferenttypesofsand

TheCBRvs lengthofcoirfibercurve fordifferent typesofsandmixedwithvarious lengthofnaturalcoirfiberofvaryingpercentageareshowninFig.8.FromtheCBRtestresults,itcanbeobservedthattheCBRvaluesincreasewithincreaseinfiberlengthuptoafiberlengthof5mm.Afterthatitdecreasesforallthethreetypesofsand.Thisincreaseismorepredominantforfinewhitishgreysand.

increases, theOMC increases forall the three typeofsand. The increase inmoisture content ismost likelytheeffectofgreaterwaterabsorptioncapacityoffibercomparedtothatofthesurroundingsand.

Fig. 7:EffectofcoirfibercontentonCBRfordifferenttypesofsand

Fig. 8 :EffectofcoirfiberlengthonCBRfordifferent typesofsand

6. CONClUSiONS

Asa result of systematic and exhaustic experimentalinvestigation in compaction characteristic andCBRvalueofdifferentsandsmixedrandomlywithcoirfibersof varying lengths and percentages, the followingconclusionsmaybedrawn.

1. Forthealltypesofsandsused,MDDdecreasesandOMCincreaseswiththeincreaseofrandomlymixingCoir fiberwithin the rangeof different parametersstudied.

2. ThereisaconsiderableincreaseintheCBRvaluefor theall typessandsused i.e.Finebrownsand,Mediumbrown sand, andFinewhitish grey sandwhenmixingwithrandomlydistributednaturalCoirfiber, initiallyupto1 to1.5%,whereafter theCBRvaluedecreases.

3. CBRvalueismaximumforfiberlengthof5mmforCoirfibers independentof typesofsandusedandoptimumfiber inclusion is 1.5%of the dryweightof sand for Coir fiber beyondwhichCBR valuedecreases.

4. ForFinebrownsandandFinewhitishgreysandusedinthisinvestigationremarkableincreaseintheCBRvaluesisobservedwhenCoirfibersof0.5cmlengtharemixedwith1.5%byweightofthesand.ThesetypesofsandsinsuchcombinationwithnaturalCoirfibershavingCBRgreater than12%maybecomethebestsuitableassubbasematerial.

27


7. aBBrEViaTiONS

Thefollowingsymbolsareusedinthispaper:

CBR=Californiabearingratio;

MDD=Maximumdrydensity;

OMC=Optimummoisturecontent;

rEFErENCES

1. Consoli N.C., Prietto P.D.M. and Ulbrich L.A.(1998):InfluenceofFiberandCementAdditiononBehaviorofSandySoil,JournalofGeotechnicalandGeoenvironmental Engineering, ASCE, Vol.124,no.12,pp.1211-1214.

2. Freitag,D.R.1986.“Soilrandomlyreinforcedwithfibers”.JournalofGeotechnicalandGeoenvironmentalEngineering,ASCE,Vol.112,no8,pp.823-826.

3. IS 2720 (Part VII) -1980,Determination ofWatercontent–drydensityrelationusinglightcompaction.BureauofIndianStandards,NewDelhi,India.

4. IS2720(PartXVI)-1987,LaboratorydeterminationofCaliforniaBearingRatio.BureauofIndianStandards,NewDelhi,India.

5. Jain,P.K.,Jain,R.andKumar,R.(2003)“Behaviourofexpansiveblackcottonsoilmixedwithnylonfibre”,Proc.IndianGeotechnicalConference,Roorkee,Vol-1,pp.389-392.

6. Kaniraj, S. R. and Havanagi, V. G. (2001)“Behavior of cement-stabilization fiber-reinforcedfly ash-soilmixtures. Journal ofGeotechnical andGeoenvironmentalEngineering,ASCE,Vol.127,no.7,pp.574-584.

7. Lindh andMattsson,Nina (2004) “Composite soilmadeof rubberwasteandcementstabilizedsoil”,5thinternationalconferenceofGroundImprovementTechniques,Malaysia,pp.195-202.

8. Maity,J.,Chattopadhyay,B.C.andMukherjee,S.P.(2012); “Behaviour of sandsmixed randomlywithnaturalfibers”ElectronicsJournalofGeo-technicalEngineering,Vol.17,BundL,pp.1833-1854.

9. Maity,J.,Chattopadhyay,B.C.andMukherjee,S.P.(2010);“Applicationofgeo-naturalsspoilsinsubbaseforRoadConstruction”Proc. IndianGeotechnicalConference,Vol.-I,Dec.16-18, 2010,Mumbai, pp617-620.

10.Michalowski,R.L.andZhao,A.1996.“Failureoffiber-reinforcedgranular soils”. Journal ofGeotechnicalandGeoenvironmentalEngineering,ASCE,vol.122,no.3,pp.226-234.

11.Pazare, K.S., Chatterjee, P. (2002) “Behaviourof silty soil reinforcedwith randomly distributedfibers”.ProceedingsofNational seminar onRoadTransportation in India: Emerging Trends andTechniques,September,12-13,2002,IIT,Kharagpur,pp.3.41-3.48.

12.Ranjan,G.,Vasan,R.M.andCharan,H.D.1996.“Probabilistic analysis of randomly distributedfiber reinforced soil”. Journal ofGeotechnical andGeoenvironmentalEngineering,ASCE,vol.122,no.6,pp.419-426.

13.Rao,V.G.andBalan,K.(2000).“CoirGeotextiles—APerspective”,NBCCMDCJournal,Vol.13,pp.11–15.

14.Santoni,R.L.andWebster,S.L.(2001)“AirfieldandRoadsconstructionusingfiberstabilizationofsands”Journal of TransportationEngineering,ASCE,Vol127no3p-96-104.

15.Santoni,R.L.andWebster,S.L.(2001)“EngineeringPropertiesofsand-fibermixtureforRoadConstruction”Journal of Geotechnical andGeoenvironmentalEngineering,ASCE,vol.127,no.3,pp.258-268.

16.Singh, V. andPrasad,H.S. (2004) “Use of sandlayerassubbasematerialsinroadconstructiononalluvialsoil”,Proc.IndianGeotechnicalConferenceonGround Engineering: Emerging Techniques,WarangalVol1,pp.494-496.

17.Varghese, P.J.B. and T. JoseBabu (1989) “SoilReinforcement using Coconut Fibres and coirgeotextiles,”Proc.1stKeralaScienceCongress,pp.279-282



INterNAtIoNAL GeosYNthetICs soCIetY

TheInternationalGeosyntheticsSociety(IGS)wasfoundedinParis,on10November1983,byagroupofgeotechnicalengineersandtextilespecialists.TheSocietybringstogetherindividualandcorporatemembersfromallpartsoftheworld,whoareinvolvedinthedesign,manufacture,sale,useortestingofgeotextiles,geomembranes,relatedproductsandassociatedtechnologies,orwhoteachorconductresearchaboutsuchproducts.

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products,e.g.bypromotingseminars,conferences,etc. • topromoteadvancementofthestateoftheartofgeotextiles,geomembranesandrelatedproductsandof

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mEmBErShipMembershipofIGSisprimarilyorganisedthroughnationalChapters.Mostindividualmembers(94%)belongtotheIGSthroughChapters.Chapterparticipationallowsmemberstobeinformedabout,andparticipatein,localandregionalactivitiesinadditiontoprovidingaccesstotheresourcesoftheIGS.IGSOffersthefollowingcategoriesofmembership:individual IndividualmemberbenefitsareextendedtoeachandeveryindividualmemberoftheIGSincludingChapterMembers.AdditionalchapterbenefitsareprovidedtoIndividualMemberswhojointheIGSthroughachapter.IndividualMemberBenefitsinclude: • amembershipcard • anIGSlapelpin • on-lineaccesstotheIGS Membership Directory,publishedyearly,withfulladdresses,telephone,emailand

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GreeceHGS,GreekChapter(2005)President:[email protected]:undercompletereconstruction!

indiaIndianChapter(1988)President:[email protected]

indonesiaINA-IGS,theIndonesianChapter(1992)President:[email protected]@gmail.com

iranIranianChapter(2013)President:[email protected]@yahoo.com

italyAGI-IGS,theItalianChapter(1992)President:Dr.Ing.DanieleCazzuffiagi@associazionegeotecnica.itwww.associazionegeotecnica.it/~agi/

JapanJapaneseChapter(1985)Chairman:[email protected]/jcigs/

KazakhstanKazakhstanianChapter(2012)President:[email protected]

koreaKC-IGS,TheKoreanChapter(1993)President:[email protected]

MexicoMexicanChapter(2006)President:[email protected]@igsmexico.orgwww.igsmexico.org

The NetherlandsNetherlandsChapter(1992)President:[email protected]

North americaNorthAmericanGeosyntheticsSociety(NAGS)(Canada,USA)(1986)President:RobertMackey,[email protected]

NorwayNorwegianChapterofIGS(2008)President:[email protected]

pakistanPakistanianChapterofIGS(2011)President:[email protected]

peruPeruvianChapter(2001)President:Eng.AugustoV.Alzawww.igsperu.org

philippinesPhilippineChapter(2007)President:[email protected][email protected]

polandPolishChapter(2008)Chairman:[email protected]

portugalPortugueseChapter(2003)President:[email protected]

romaniaRomanianChapter(1996)President:[email protected]@utcb.ro

31


russiaRussianChapterofIGS(RCIGS,2008)President:[email protected]

SlovakiaSlovakianChapterofIGS(2011)President:[email protected]

South africaSouthAfricanChapter(1995)President:[email protected]@englining.co.zawww.gigsa.org

SpainSpanishChapter(1999)President:[email protected]

ThailandThaiChapter(2002)President:[email protected]/acsig/igs-thailand

TurkeyTurkishChapter(2001)President:[email protected]

United kingdomU.K.Chapter(1987)Chairman:[email protected]

West Pacific Regional ChapterWestPacificRegionalChapter(1997)President:Dr.Liang,[email protected]

iGS OFFiCErS

president JorgeG.Zornberg,PhD.,P.E.TheUniversityofTexasatAustinCivil,Architectural&EnvironmentalEngineeringDepartment,1Univ.StationC1792RmECJ9,227GAustin,Texas78712-0280USATel:1/5122323595Fax:1/5124716548Email:[email protected]

Vice-president Dr.RussellJonesGolderAssociates(UK)LimitedAttenboroughHouse,BrownsLaneBusinessPark,Stanton-on-the-Wolds,Notting-hamshire,NG125BLUNITEDKINGDOMTel:441159371111Fax:441159371100Email:[email protected]

immediate past-president Prof.FumioTatsuokaTokyoUniversityofScienceDept.ofCivilEngineering,2641Yamazaki,NodaCityChibaPrefecture278-8510JAPANTel:81/4712298190Fax:81471239766Email:[email protected]

Treasurer PeterLeggConsultingPrincipal,Geo-EnvironmentalEngineers288thAvenue,Northmead,Benoni,1501SOUTHAFRICATel:27(0)114251197Fax:27(0)114251197Email:[email protected]

Secretary ElizabethPeggsgeosynthetica.net1934CommerceLane,Suite4Jupiter,Florida,USA33458Tel+1561768-9487Fax+15618287618Email:[email protected]

International Geosynthetics Society


IGs NeWs

CONFErENCE rEpOSiTOry SErViCE aVailaBlE ONliNE FOr iGS mEmBErS

TheIGSispleasedtoannouncethelaunchoftheConferenceRepositorySer-vicetothemembers.Thepapersfromdifferentgeosyntheticconferencesarescannedandplacedonthewebsitewww.geosyntheticssociety.org.

IGSmembersmaygetaccess todifferentproceedingsusing the link“Proceed-ingsLibrary”under theMemberToolsonthemainpageofthewebsite.Somehelpfulinstructionsonhowtousetheresourcesaregivenonthemainpageitself.

ThemembersoftheTC-SoilReinforcementhaveobtainedthecopyrightper-missionsfromtheoriginalpublishersforlaunchingthepapersonwebsite.

Currently,thefollowingproceedingsareavailableontherepository.

• Proc.ofthe1stInternationalConferenceontheuseoffabricsinGeotechnics(1977),Paris,France

• Proc.ofthe2ndInternationalConferenceonGeosynthetics(1982),LasVegas,USA

• Proc.ofthe3rdInternationalConferenceonGeotextiles(1986),Vienna,Austria

• Proc.ofthe7thInternationalConferenceonGeosynthetics(2002),Nice,France

• Proc.ofthe9thInternationalConferenceonGeosynthetics(2010),Guaruja,Brazil

• Proc.ofEarthReinforcementConference(1992)ISKyushu,Japan



• Proc.ofEuroGeo-I(1996),Maastricht,TheNetherlands

Thepapersareuploadedunderdifferentvolumesoftheconferences.Titleofeachpaperisthenameusedtolistthepapersonthesiteforeaseofidentification.Eachpaperistaggedwithdifferentkeywordslikeauthornames,conferencename,conferenceplace,sessionname,publisherandtheyear.Thepapersaresearchableunderthedifferentkeywords.Thekeywordsearchwillenablefindingallrelevantpapersintheentireconferencerepository.

Allpapersonthesitemaybeprotectedbycopyrightregulations.Membersandnon-membersofIGSmustadheretoallcopyrightrulesandregulationsastheypertaintoallthedocumentsprovidedonthewebsite.

iGS aWardS: Call FOr NOmiNaTiONS 2010 – 2013 – NOmiNaTiONS dUE 31 JaNUary 2014

IGSAwardswillbegrantedin2014toindividualsorgroupsofindividualswhohavemadeanoutstandingcontributiontothedevelopmentanduseofgeotextiles,geomembranes,relatedproducts,orassociatedtechnologiesthroughtheirscientificandtechnologicalachievements.Forexample,anawardcanbegivenfordesignandconstructionofastructure;publicationofatechnicaldocument(paper,book,article,manual);completionofare-searchprogram;developmentofnewproductsandtechniques.

TheAwardsrecognizetheachievementscompletedand/orthevalidityofwhichhavebeendemonstratedduringthefour-yearperiodproceedingtheyearoftheAward(i.e.,2010through2013inclusive).

ThewinningentrieswillbepublicizedinIGSNews,inaspecialpressreleaseontheIGSwebsiteandinotherIGSpublications.

Timeline and deadlines

NominationsmustbereceivedbytheIGSSecretarynolaterthan31January2014.

Thedeadlineforreceiptofawardcandidatepresentationpackagesis31March2014.

PresentationpackageswillbeforwardedbytheSecretariattotheAwardCommitteeby15April2014fortheCommitteetoreviewandtofinalizetheirdecisions,draftcitationsandreport.

33


Awardswillbepresentedat10ICG,inBerlin,Germany,on21to25September2014.

There are Two iGS awards

• TheYoungIGSMemberAchievementAwardThisAwardisforIGSMemberswhoarelessthan36yearsofageon31December2013.

• TheIGSAward

ParticipantsofthemeetingbetweenWRAandIGS.Fromlefttoright:Dr.HectorBonillaCuevas,Ing.IgnacioNarezoLarios,Ing.OscarDeBuenRichkarday(WRAPresident),Dr.JorgeG.Zornberg(IGSPresident),Ing.GuillermoLopezMelladoandIng.GuillermoJesusLopez(notinthepicture).

Theawardswillconsistofaspeciallycommissionedmedalandadiploma.

IfagroupsubmissionismadefortheYoungIGSMemberAchievementAward,allmembersofthegroupshouldsatisfytheagerequirementforthis.Ifthisrequirementisnotsatisfied,theentiregroupwillbenoteligablefortheYoungIGSMemberAchievementAward.Ifacandidate,individualorgroup,satisfiestheagerequirementfortheYoungIGSMemberAchievementAward,theentrysubmittedbythiscandidatewillbeconsideredforbothawards(unlessrequestedotherwisebythecandidate).However,acandidatemayonlyreceiveoneaward.

aNNOUNCEmENT FOr ThE rECipiENTS OF ThE 2013-2014 aCadEmiC yEar GSi FEllOWShip aWardS

TheGSIBoardofDirectorshasmadetheirselectionsforthisyear’sGSIFellowshipawardsfromanumberofproposalsfromuniversitiesaroundtheworld.Theprogramrecognizesandsupportsoutstandinggraduatestudentsstudyinggeosynthetics.Requestsforproposals(RFP’s)fortheupcomingseventhyearoftheprogramwillbeannouncedthiswinter.Inordertobeeligible,studentsmustfocusonageosynthetictopic,havepassedtheir candidacy examination, and be recommended by their advisor. The recipients for the 2013-’14GSIFellowshipAwardsareasfollows:

Class 6(a) – 1st Year Funding at $10,000 per Student

No. Name University advisor Topic1-13 JongwanEun Univers i ty of

WisconsinCraigBenson TransportParametersinCoextrudedGeomembrane

ContainingEthyleneVinyl-Alcohol2-13 YuQian Univers i ty of

IllinoisErolTutumluer Geogrid-BallastInteractionandGeogridApplicationin

RailroadReinforcementusing Image-aidedDiscreteElementMethod

Class 5(b) – 2nd Year Funding at $5,000 per Student

No. Name University advisor Topic2-12 XunchangFei Univers i ty of

MichiganDimitriosZekkos

ImpactofMunicipalSolidWasteBiodegradationonSeparatorGeotextile

Class 4(c) – 3rd year Funding at $5000 per Student

No. Name University advisor Topic3-11 FelixJacobs RWTHAachen

UniversityMartinZiegler LargeScaleBiaxialCompressionTestingofGeogrid

ReinforcedSoil

PleasecontactJamieKoernerat [email protected] foradditional informationon thestudentsand theirrespectiveprojectsorgotowww.geosynthetic-institute.org/gsifellows.htmforacompletehistoryofthefellowshipprogram.


INdIAN ChAPter oF INterNAtIoNAL GeosYNthetICs soCIetY

iNTrOdUCTiON

Intheyear1985,CentralBoardofIrrigationandPower,(CBIP)aspartofitstechnologyforecastingactivitiesidentifiedgeosyntheticsasanimportantarearelevanttoIndia’sneedforinfrastructuredevelopment,includingroads.

AfterapprovalofIGSCouncilfortheformationofIndianChapterinOctober1988,theIndianChapterofIGSwasgotregisteredunderSocietiesRegistrationActXXIof1860ofIndiainJune1992astheCommitteeforInternationalGeotextileSociety(India).TheChapterhassincebeenrenamedasInternationalGeosyntheticsSociety(India),inviewoftheparentbodyhavingchangeditsnamefromInternationalGeotextilesSocietytoInternationalGeosyntheticsSociety.

OBJECTiVES

- tocollectanddisseminateknowledgeonallmattersrelevanttogeotextiles,geomembranesandrelatedproducts,e.g.bypromotingseminars,conferencesetc.;

- topromoteadvancementofthestate-of-the-artofgeotextiles,geomembranesandrelatedproductsandoftheirapplications,e.g.byencouraging, through itsmembers, theharmonizationof testmethods,equipmentandcriteria;and

- toimprovecommunicationandunderstandingregardingsuchproducts,e.g.betweendesigners,manufacturersandusersandespeciallybetweenthetextileandcivilengineeringcommunities.

EXECUTiVE BOard

TheExecutiveBoardoftheIndianChapterconsistsofPresident,electedbytheGeneralBody,twoVice-Presidents,withoneelectedbytheGeneralBody,andsecondVicePresidentbeingVicePresident(Civil)oftheCBIPasEx-OfficioVicePresidentand16members.Theminimumstrengthof theExecutiveBoard is07andmaximum19,includingofficebearers.

ThetermoftheExecutiveBoardistwoyearsandelectedmembersarenoteligibleformorethantwoconsecutiveterms.

TheSecretaryoftheCBIPactsasMemberSecretary,andistheChiefExecutiveoftheChapter.Director(WR),CBIPisEx-OfficioTreasureroftheChapter.

EXECUTiVE BOard 2012-2014

president

• Dr.G.V.S.SuryanarayanaRaju,Engineer-in-Chief,Roads&BuildingsDepartment,GovernmentofAndhraPradesh

Vice-presidents

• Mr.M.Venkataraman,GeotechnicalandGeosyntheticConsultant

• Vice-President(Civil)ofCBIP

immediate past president

• Dr.K.Rajagopal,Professor,DepartmentofCivilEngineering,IITMadras

hon. member • Dr.G.V.Rao,Chairman,SAGES

members: • Mr.arvind kumar,CEO,AravaliPowerCompanyPvt.Ltd.

35


• Dr.K.Balan,Professor,DepartmentofCivilEngineering,CollegeofEngineering,Trivandrum(Kerala)

• Mr.P.K.Choudhury,Incharge,GeotechCell,IndianJuteIndustries’ResearchAssociation

• Mr.Narendradalmia,CEO/Director,StrataGeosystems(India)Pvt.Ltd.

• Mr.C.R.devaraj,ManagingDirector,CharankattuCoirMfg.Co.(P)Ltd.

• Mr.AshishD.Gharpure,Director,MaccaferriEnvironmentalSolutionsPvt.Ltd.

• Mr.R.N.misra,Director(Civil),SJVNLimited

• Mr.murari ratnam,Director,CentralSoilandMaterialsResearchStation

• Dr.DasakaS.murty,AssistantProfessor,DepartmentofCivilEngineering,IndianInstituteofTechnologyBombay

• Mr.Satish Naik,CEO,BestGeotechnicsPvt.Ltd.

• Mr.Bhavannarao,EgisIndiaConsultingEngineersPrivateLimited

• Dr.JimmyThomas,Consultant(Geosynthetics),Kochi(Kerala)member Secretary • Mr.V.K. kanjlia,Secretary,CentralBoardofIrrigationandPowerTreasurer • Mr.A.C.Gupta,Director(WR),CentralBoardofIrrigation&Power

mEmBErShip EliGiBiliTy

Membership is open to individuals/institutions,whoseactivities or interests are clearly related to the scientific,technological or practical development or useof geotextiles, geomembranes, relatedproducts andassociatedtechnologies.

membership Fee

TheMembershipfeepayableoncalendaryearbasisis:

• IndividualMember Indian Rs.2,000/-

• InstitutionalMember(foronecalendaryear) Indian Rs.20,000/-

• InstitutionalMember(fortwocalendaryears) Indian Rs.35,000/-

• InstitutionalMember(forthreecalendaryears) Indian Rs.50,000/-

• Student NIL

BENEFiTS

institutional member

• 4 representatives tobemade individualmembersof IndianChapterand IGS, free frompaymentofindividualmembershipfeeofIndianRs.2,000/-permember.

• onecopyeachofthepublicationsbroughtbytheIndianChapterduringtheperiodofmembership

• discount in registration fee toeachof the representatives ineachevent tobeorganisedby the IndianChapter

• rightofusingtheIndianChapterlogoatexhibitionsandinpromotionalliterature;

• priority(byseniority)atallexhibitsorganisedbyIndianChapter;

• possibilityofjoiningaspecificinternationalcommitteeinordertodiscusstopicsofcommoninterest

• PromotionofactivitiesthroughIndianJournalofGeosyntheticsandGroundImprovement

individual member

• IGSNEWS,publishedthreetimesayear,andIndianJournalofGeosyntheticsandGroundImprovement,publishedtwotimesayear;

Indian Chapter of International Geosynthetics Society



• Informationoncurrenttestmethodsandstandards

• PreferentialtreatmentatconferencesorganisedbyIGS(India)andIGSorunderitsauspices;

• PossibilityofbeinggrantedanIGSaward.

• Discountrates:

- foranydocumentpublishedinthefuturebyIGSandIGS(India);

- atallinternational,regionalornationalconferencesorganisedbyIGS(India)andIGSorunderitsauspices;

- forthesubscriptionofthejournal“GeotextilesandGeomembranes”;

- forthesubscriptionofthejournal“GeosyntheticsInternational”.

Student member • IGSNEWS,publishedthreetimesayear,andIndianJournalofGeosyntheticsandGroundImprovement,

publishedtwotimesayear;

• informationoncurrenttestmethodsandstandards

• SpecialStudentdiscounts:

- atallinternational,regionalornationalconferencesorganisedbyIGS(India)andIGSorunderitsauspices;

- eligibilityforawards(andinparticulartheIGSYoungMemberAward)

EVENTS OrGaNiSEd/SUppOrTEd SiNCE 2000

1. Seminaron“CoirGeotextiles-EnvironmentalPerspectives”,November2000,NewDelhi

2. SecondNationalSeminaron“CoirGeotextiles–EnvironmentalPerspectives”,April2001,Guwahati,Assam

3. NationalSeminaron“ApplicationofJuteGeotextilesinCivilEngineering”,May2001,NewDelhi

4. InternationalCourseon“GeosyntheticsinCivilEngineering”,September2001,Kathmandu,Nepal

5. SecondInternationalConferenceon“WaterQualityManagement”,February2003,NewDelhi

6. Workshopon“ApplicationsofGeosyntheticsinInfrastructureProjects”,November2003,NewDelhi

7. GeosyntheticsIndia2004–ASeminarWorkshopon“GeotechnicalEngineeringPracticewithGeosynthetics”,October2004,NewDelhi

8. IntroductoryCourseonGeosynthetics,November2006,NewDelhi

9. InternationalSeminaron“GeosyntheticsinIndia–PresentandFuture”(inCommemorationofTwoDecadesofGeosyntheticsinIndia),November2006,NewDelhi

10.Workshopon“RetainingStructureswithGeosynthetics”,December2006,Chennai(TamilNadu)

11.Workshopon “Applications ofGeosynthetics –Present andFuture”, 20-21September 2007,Ahmedabad(Gujarat)

12.InternationalSeminar“GeosyntheticsIndia’08”and“IntroductoryCourseonGeosynthetics”,19-21November2008,Hyderabad

13.Seminaron“ApplicationofGeosynthetics”,22July2010,NewDelhi

14.InternationalSeminaron“ApplicationsofGeosynthetics”,12November2010,NewDelhi

15.Seminar“GeosyntheticsIndia’11”,includingAnIntroductoryCourseonGeosynthetics,22-24September2011,IITMadras

16.GEOINFRA2012–AConvergenceofStakeholdersofGeosynthetics,25-26August2012,Hyderabad

17.Seminaron“GroundControlandImprovement”,20-21September2012,NewDelhi

18.Workshopon“GeosyntheticReinforcedSoilStructures-Design&Construction”,17-18October2012,NewDelhi

19.Seminaron“LandfillDesignwithGeomembrane”,27November2012,NewDelhi

37


20.Seminaron“SlopeStabilizationChallengesinInfrastructureProjects”,29-30November2012,NewDelhi

21.Seminaron“ApplicationofGeosyntheticinInfrastructureProjects”,20-21June,2013,Bhopal

liST OF pUBliCaTiONS

1. UseofGeosynthetics–IndianExperiencesandPotential–AStateofArtReport

2. NationalWorkshoponRoleofGeosyntheticsinWaterResourcesProjects

3. Monograph on Particulate Approach to Analysis of Stone Columns with and without GeosyntheticsEncasing

4. RecentDevelopmentsintheDesignofEmbankmentsonSoftSoils

5. Proceedingsof2ndInternationalWorkshoponGeotextiles

6. DirectoryofGeotextilesinIndia–Vol.I

7. AnIntroductiontoGeotextilesandRelatedProductsinCivilEngineeringApplications

8. EngineeringwithGeosynthetics

9. GroundImprovementwithGeosynthetics

10.GeosyntheticsinDamEngineering

11.ErosionControlwithGeosynthetics

12.DirectoryofGeosyntheticsinIndia.Vol.II

13.Bibliography–TheIndianContributiontoGeosynthetics

14.WasteContainmentwithGeosynthetics

15.GeosyntheticApplicationsinCivilEngineering-AShortCourse

16.CaseHistoriesofGeosyntheticsinInfrastructureProjects

17.Geosynthetics–RecentDevelopments(CommemorativeVolume)

18.ProceedingsofInternationalSeminaron“GeosyntheticsinIndia–PresentandFuture”

19.ProceedingsoftheWorkshopon“ApplicationsofGeosynthetics–PresentandFuture”,20-21September2007,Ahmedabad

20.DirectoryofGeosyntheticsinIndia–2008

21.Proceedingsof“GeosyntheticsIndia’11”

22.EarthReinforcement–DesignandConstruction

SECrETariaT

AllcorrespondencesrelatingtotheSocietyshouldbeaddressedto:

mr. V.k. kanjliaSecretaryCentralBoardofIrrigation&PowerMalchaMarg,Chanakyapuri,NewDelhi110021,India

Contact Person: Mr. Uday Chander, Senior ManagerPhone :+91-11-26115984,Extn.114Fax :+91-11-26116347E-Mail :[email protected];[email protected]

Indian Chapter of International Geosynthetics Society


Activities of Indian Chapter

SilVEr JUBilEE CElEBraTiONS

INterNAtIoNAL sYmPosIUm

GeosYNthetICs INdIA - 2013ANd

semINAr oN “GeosYNthetICs BArrIer eNGINeerING”23-25 October 2013, New Delhi, India

TomarktheSilverJubileeoftherecognitionofIndianChapterofIGSbyIGSCouncil,in1988,IndianChapterisorganizingtheInternationalSeminar“GeosyntheticsIndia-2013”,includingahalfdaySpecialSessionon“RetrospectandFutureofGeosyntheticsinIndia”.

On23October2013,theIndianIGSChapterwillhold,aone-daySeminaron“GeosyntheticBarriers”,aspartofitsSilverJubileeCelebrations.

Theseminarwillfocusoncurrentnewresearchtopicsforgeosyntheticbarriers,suchasgeomembranes,geosyntheticclayliners(GCLS),multi-componentGCLsandbituminousliners,theuseofthesebarriersinvariousapplicationsandthepracticalinclusionoftheseengineeredbarriersforlandfills,mining,coalcombustionresidualsitesandotherindustrialapplications.Advantagesanddisadvantagesofalternativetechnologiesqualityaswellascontrolplansfortheirestablishmentwillbediscussed.

Theregistrationfeeforparticipationintheeventisasfollows:

•Seminar on “Geosynthetics Barrier Engineering”, 23 October 2013

MembersofIGS/CBIP INR4,500/[email protected]%Non-Members INR5,000/[email protected]%Researchers/Academicians/Students INR2,500/[email protected]%

•Symposium “Geosynthetics India’2013”, 24-25 October 2013


•Combined Registration Fee for the Seminar and Symposium, 23-25 October 2013


Incaseof03nominationsfromanorganization,20%discountintheregistrationwillbeoffered.

SympOSiUm SECrETariaT

CentralBoardofIrrigation&PowerMalchaMarg,Chanakyapuri,NewDelhi110021,India

Contact Person: Mr. V.K. Kanjlia, SecretaryPhone : +91-11-26115984/26111294Fax : +91-11-26116347E-mail : [email protected];[email protected] : http://www.cbip.org


SeminarAPPLICAtIoNs oF GeosYNthetICs IN

INFrAstrUCtUre ProJeCts20-21 June 2013, Bhopal (Madhya Pradesh), India

Mr. A.C. Gupta delivering the Welcome Address. Other diginitaries on the dais (L to R) are: Mr. M. Venkataraman, Mr. Akhilesh Agrawal, Mr. M.G. Choubey and Mr. K.M. Singh.

In theyear1985, theCentralBoardof IrrigationandPower (CBIP) as part of its technology forecastingactivit ies identif ied geosynthetics as importantand relevant to India’s need for infrastructuredevelopment.

Todaytheuseofgeosyntheticsis increasinglybeingaccepted as constructionmaterial in different fieldsof civil engineering not only in developed countriesbutalsointhedevelopingcountrieslikeours.Recentdevelopments in synthetic and natural fabrics haveprovided enormous fillip in the use of geosyntheticsmaterialsandanentirelynewspectrumofapplicationshasemerged.

Central Board of Irrigation and Power (CBIP) andIndian Chapter of IGS jointly organized a non-residentialSeminaron“ApplicationsofGeosyntheticsinInfrastructureProjects”atHotelPalashResidency,T.T. Nagar, Bhopal during 20-21 June 2013, withan objective to deliberate and promote the fieldapplicationsofgeosynthetics.

FollowingtopicswerediscussedduringtheSeminar:

• MaterialsUsedforManufactureofGeosyntheticsandRelatedProducts–TheirProperties,TestingandEvaluation

• ClassificationofGeosynthetics

• MultipleApplicationsofGeosynthetics

• SafetyAspectsofStructuresDesignedbyUseofGeosynthetics

TheSeminarwasinauguratedbyMr.M.G.Choubey,Engineer-in-Chief, Water Resources Department,Government of Madhya Pradesh. Mr. AkhileshAgrawal,Engineer-in-Chief,PublicWorksDepartment,GovernmentofMadhyaPradeshandMr.K.M.Singh,Chief Executive Director, NHDC Limited were theGuestsofHonour.

DuringtheInauguralSession,Mr.A.C.Gupta,Director(WR), CBIP and Treasurer of the IndianChapter ofIGS welcomed the dignitaries on the dais and thedelegates. Mr. M. Venkataraman, Vice President,IndianChapterofIGSbrieflydescribedtheobjectivesoftheSeminar.

Intotal65participantsfrom20organizations,includingfromBhutan,participatedintheSeminar.

Theeminentspeakers,fromtheindustryandresearch,includedthefollowing:

• Mr.AdrianAnderson,GeneralManager,NehemiahReinforcedSoil(India)PvtLtd.

• Dr. T.G. Antony Balan, Department of CivilEngineering,KarunyaUniversity

• Mr. Ashish D. Gharpure, Director, MaccaferrriEnvironmentalSolutionsPvt.Ltd.

• Mr.SatishNaik,CEO,BestGeotechnicsPvt.Ltd.

• Dr.K.Rajagopal,DepartmentofCivilEngineering,IITMadras

• Ms.RumkiSaha,NationalJuteBoard

• Mr . M. Venkataraman, Geotechnica l andGeosyntheticConsultantandVicePresident,IndianChapterofIGS

• Mr.SaurabhVyas,DesignHead,TechFab IndiaIndustriesLtd.

The Seminar was appreciated by the participants.The successful applications of geosynthetics incivil engineering, namely, construction of dam,embankments, canals, approach roads, runways,railwayembankments,retainingwalls,slopeprotectionworks,drainageworks,rivertrainingworks,seepagecontrol, hazardouswastemanagement, etc., helpedthem to understand the useful applications ofgeosyntheticsandpaved theway for themtouse it,whereverpossible,intheirfieldofwork.


INdIAN JoUrNAL oF GeosYNthetICs ANd GroUNd ImProVemeNt

GUidEliNES FOr aUThOrS

This journal aimstoprovideasnapshotofthelatestresearchandadvancesinthefieldofGeosynthetics.Thejournaladdresseswhatisnew,significantandpracticable.indian Journal of Geosynthetics and Ground improvement ispublishedtwiceayear(January-JuneandJuly-December)byIndianJournals.Com,NewDelhi.TheJournalhasbothprintandonlineversions.Beingpeer-reviewed,thejournalpublishesoriginalresearchreports,reviewpapersandcommunicationsscreenedbynationalandinternationalresearcherswhoareexpertsintheirrespectivefields.

Theoriginalmanuscriptsthatenhancethelevelofresearchandcontributenewdevelopmentstothegeosyntheticssectorareencouraged.TheworkbelongingtothefieldsofGeosyntheticsareinvited.The journal is expected to help researchers,technologistandpolicymakersinthekeysectorofGeosyntheticstoimprovecommunicationandunderstandingregardinggeotextiles,geomembranesandrelatedproductsamongdesigners,manufacturersandusersThemanuscriptsmustbeunpublishedandshouldnothavebeensubmittedforpublicationelsewhere.Therearenopublication Charges.

1. Guidelines for the preparation of manuscripts for publishing in “indian Journal of Geosynthetics and Ground improvement”

TheauthorsshouldsubmittheirmanuscriptinMS-Word(2003/2007)insinglecolumn,doublelinespacing.ThemanuscriptshouldbeorganizedtohaveTitlepage,Abstract,Introduction,Material&Methods,Results&Discussion,Conclusion,andAcknowledgement.Themanuscriptshouldnotexceed16pagesindoublelinespacing.

Submission of manuscript:

Themanuscriptmustbesubmitted indocandpdf to theEditorasanemailattachment [email protected]. Theauthor(s)shouldsendasigneddeclarationformmentioningthat,thematterembodiedinthemanuscriptisoriginalandcopyrightedmaterialusedduringthepreparationofthemanuscripthasbeendulyacknowledged.Thedeclarationshouldalsocarryconsentofalltheauthorsforitssubmissiontoindian Journal of Geosynthetics and Ground improvement.Itistheresponsibilityofcorrespondingauthortosecurerequisitepermissionfromhisorheremployerthatallpaperssubmittedareunderstoodtohavereceivedclearance(s)forpublication.TheauthorsshallalsoassignthecopyrightofthemanuscripttotheIndianChapterofInternationalGeosyntheticsSociety.

peer review policy:

ReviewSystem: Every article is processed by amasked peer review of double blind or by three refereesandeditedaccordinglybeforepublication.Thecriteriausedfortheacceptanceofarticleare:contemporary relevance, updated literature, logical analysis, relevance to the global problem, sound methodology, contribution to knowledge and fairly good English.Selectionofarticleswillbepurelybasedontheexperts’viewsandopinion.AuthorswillbecommunicatedwithinTwomonthsfromthedateofreceiptofthemanuscript.TheeditorialofficewillendeavortoassistwherenecessarywithEnglishlanguageeditingbutauthorsareherebyrequestedtoseeklocaleditingassistanceasfaraspossiblebeforesubmission.Paperswithimmediaterelevancewouldbeconsideredforearlypublication.Thepossibleexpectationswillbeinthecaseofoccasionalinvitedpapersandeditorials,orwhereapartialorentireissueisdevotedtoaspecialthemeundertheguidanceofaGuestEditor.

The Editor-in-Chief may be reached at: [email protected]


CALeNdAr oF eVeNts1. ExperimentalMicromechanicsforGeo-materialsHongKong,China(HongKongS.A.R.)23-24May2013E-mail:owlam@

hku.hk

2. 18thSoutheastAsianGeotechnicalConferencecumInauguralAGSSEASingapore29-31May2013E-mail:[email protected]

3. SecondInternationalSymposiumonGeotechnicalEngineeringforthePreservationofMonumentsandHistoricSitesNapoli,Italy30-31May2013E-mail:[email protected]

4. 5th InternationalSymposiumonGe-otechnicalEngineering,DisasterPre-ventionandReduction, andEnviron-mentallySustainableDevelopmentIncheon,SouthKorea15-17May2013E-mail:[email protected]

5. ThefirstinternationalconferenceonFoundationandSoftGroundEngineer-ingChallegesinMeKongDeltaBinhDuong,Vietnam5-6June2013E-mail:[email protected]/

6. Recentadvancesandchallenges ingeotechnicalearthquakeengineeringMini-Symosiumwithin the frameworkof:4thInternationalConferenceonComputationalDynamics&EarthquakeEngineering(COMPDYN2013)Kosisland,Greece12–14June2013E-mail:[email protected]@science.tuc.grhttp://compdyn2013.org/en/static/accepted-minisymposia_en.aspx

7. TC215ISSMGE-InternationalSym-posiumon“CoupledPhenomenainEnvironmentalGeotechnics(CPEG)-fromtheoreticalandexperimental research topracticalapplications”1 -3July2013Torino, ItalyE-mail:[email protected]@polito.itwww.tc215-cpeg-torino.org

8. FifthInternationalYoungGeotechnicalEngineers’Conference(5iYGEC’13)Paris,France31August-01September2013E-mail:[email protected]/EN/events.php?IDManif=696&IDModule=21

9. 18thInternationalConferenceforSoilMechanicsandGeotechnicalEngineer-ingParis,France2-6September2013E-mail:[email protected],[email protected]

10. REMTECHEXPO2013RemediationTechnologiesandRequalificationoftheTerritoryExhi-bition-7thEditionFerrara,Italy18-20September2013E-mail:[email protected]

11. InternationalSymposiumonDesignandPracticeofGeosynthetic-ReinforcedSoilStructuresBologna,Italy14-16October2013E-mail:[email protected]://www.civil.columbia.edu/bologna2013

12. InternationalConferenceGeotechnics inBelarus:ScienceandPracticeMinsk,Belarus 23 - 25October 2013E-mail:[email protected],[email protected]

13. GeosintecIberia1Seville,Spain5-6November2013www.geosinteciberia.com

14. The19thNZGSSymposium“HangingbyaThread–Lifelines, InfrastructureandNaturalDisasters”Queenstown,NewZealand20-23November2013E-mail:[email protected]/

15. 10thInternationalSymposiumofStruc-tures,GeotechnicsandConstructionMaterialsSantaClara,VillaClara,Cuba26-29November2013E-mail:[email protected],[email protected]

16. GEOTECHANOI 2013 “Geotechnics forSustainableDevelopment”Hanoi, Vietnam28 - 29November 2013E-mail:[email protected]

17. The2ndAfricanRegionalConferenceonGeosyntheticsGeoAfrica2013Accra,Ghana18 -20November2013E-mail:[email protected]

18. 8thInternationalConferenceonPhysicalModellinginGeotechnics2014(ICPMG)Perth,WesternAustralia,Australia14-17January2014E-mail:[email protected]://icpmg2014.com.au/

19. 8thEuropeanConferenceonNumericalMethodsinGeotechnicalEngineering(NUMGE14)Delft,Netherlands,The18-20June2014E-mail:[email protected]

20. TC204ISSMGEInternationalSymposi-umon“GeotechnicalAspectsofUnder-groundConstructioninSoftGround”-IS-Seoul2014Seoul,Korea25-27August2014E-mail:[email protected]

21. 10th InternationalConferenceonGeosyntheticsBerlin,Germany21–25September2014E-mail:[email protected]

22. 33rdBaugrundtagungwithExhibition„Geotechnik“Berlin,Germany23–26September2014www.dggt.de


CoIr BoArd

TheCoirBoardisastatutorybodyestablishedundertheCoir IndustryAct,1953forpromotingtheoveralldevelopmentof thecoir industryandupliftmentof the livingconditionsofworkersengagedinthistraditionalindustry.ItisfunctioningundertheMinistryofMSMEofGovt.ofIndia.TheBoardconsistsof a full-timeChairman,ProfGBalachandranand39members, asprovided inSection4oftheCoirIndustryAct,1953,representingallstakegholdersincoirindustry.ThefunctionsofCoirBoard for the development of coir industry, inter-alia, include undertaking scientific, technologicaland economic research and development activities; collection of statistics relating to exports andinternalconsumptionofcoirandcoirproducts;developmentofnewproductsanddesigns;publicityforpromotionofexportsandinternalsales;marketingofcoirandcoirproductsinIndiaandabroad;preventionofunfaircompetitionamongproducersandexporters;assistanceinestablishmentofunitsforthemanufactureofproducts;promotionofco-operativeorganizationsamongproducersofhusk,coirfibre,coiryarnandmanufactures,etc.

The Research and Development activities of the Board are carried out through the two researchinstitutes; the Central Coir Research Institute, Kalavoor and Central Institute of Coir Technology,Bangalore.TheCentralCoirResearchInstitute,Alleppeywasestablishedin1959andtheCentralInstituteofCoirTechnology,Bangalore in1980. The identificationofnewuserareas forpotentialutilizationofcoir,coirwaste,coirpithandimprovementsinprocessingforbetterqualityaretheareasofspecialattention. TheCoirTestingLaboratorieshavebeensetupatPollachi,TamilNaduandBhubaneswar,Orissatocatertothetestingrequirementofthissector.It’salsohavingfiveregionaloffice,fivesub-regionaloffice,oneNationalTraining&DesignCentre,oneCoirMarkSchemeOffice,OnePower-loomCoirFactory,onedisplaycentreatNewDelhiand30showrooms.

TheCentralCoirResearchInstitute(CCRI)ofCoirBoardhasundertakenafewcollaborativestudieswiththeCochinUniversityofScienceandTechnology(CUSAT),CollegeofEngineeringandTechnology(COET),KeralaandNational InstituteofTechnology(NIT),Thiruchirapally toestablish theusesofcoirgeotextilesforconstructionofruralunpavedandpavedroads.

BasedonthestudiescarriedoutatlaboratorylevelandfieldlevelbytheCCRIincollaborationwiththeaboveinstituteshavingexpertiseintheconstructionofroadsinIndia,theIndianRoadsCongress(IRC)hasgivenaccreditation to theuseofcoirgeotextiles foruse in theconstructionof roads forwhichtheCCRIhasbeenidentifiedasanodalinstitute.

InthelightofaccreditationofIRC,theNationalRuralRoadsDevelopmentAgency(NRRDA)ofGovt.of IndiahasauthorizedtheCCRItousecoirgoetextiles in theconstructionofroads, in9statesofthecountry,foratotallengthof450kmsinthefirstphase.Basedonthis,collaborativeprojectshavebeenundertakenwithCollegeofEngg.&Technology,Trivandrum,NIT,Calicut,NIT,Trichy,MANIT,Bhopalandtheprojectsaregoingon.

TheCoirBoardisparticipatingregularlyintheInternationalErosionAssociationConferencesbeingheldinUSA.TheBoardhasarrangedabout40demonstrationsonapplicationsoncoirgeotextilesagainstsoilerosiononslopesinthecountrywhicharewelldocumented.ThescientistsofthetworesearchinstitutesoftheBoardhavepresented/publishedpapersintheinternationalconferencesworldwideandparticipatedinanumberofrenownedexhibitionstodemonstratetheuseofcoirgeotextiles.

TheCoirBoardhasestablishedatestinglaboratoryforcoirgeotextilesattheCentralCoirResearchInstitute,Alleppey,Kerala that is listed in thewebsiteofASTM[AmericanSociety forTestingandMaterials]InternationalDirectoryofTestingLaboratories.

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Profile of Institutional Member of Indian Chapter

43


CLImAX sYNthetICs PVt. Ltd.

ClimaxSyntheticsPvt.Ltd.isanISO9001:2008certifiedcompanydedicatedtothecauseof Environmental protection being one of the leadingmanufacturers and installers ofWideWidthPELiners/Geo-Membrane,U.V.films,Cap-Covers,Tarpaulin,HDPEPipes&GeosyntheticsinIndiafromalmostfourdecades.Strengthenedbyourvastexperiencein the field supported by skilled workforce and state-of the-art plant &machinery wesuccessfullycatertotheneedsofourvaluedcustomersinthewholelength&breadthofthenation.

Climax Synthetics Pvt. Ltd. had been privileged to be associated with the IndianPetrochemicalsCorporation Ltd., as their accredited processors for 18 years till 2002.DuringourassociationwithIPCL,wehadbeenmanufacturingandsupplyingPElinerstovariouscanalprojectslikeIndiraGandhiNaharProject,RajghatCanalProjectandSardarSarovarNarmadaNigamLimited,and for thevariousotherapplicationssuchasWaterReservoir,PondLining,Agriculture,Postharvestingcropprotectionetc.ClimaxSyntheticsPvt.Ltd.havesuccessfullyexecutedmanySolidWasteLandfillsforIndustriesaswellasforMunicipalCorporations.

ApartfromindigenouslymanufacturingHDPEGeo-Membrane/Linerupto2mmthicknessandHDPEPipesforlandfillapplications,ClimaxSyntheticsPvt.Ltd.alsosupply&InstallGeo-Textiles,GeosyntheticsClayLiner,Geo-netandotherGeo-SyntheticsmaterialfromthereputedmanufacturerworldwidewhichmakesClimaxSyntheticsPvt.Ltd.a“OnestopshopforallyourGeo-Syntheticneeds”.

ClimaxSyntheticsPvt.Ltdhaveexecutedmorethan30Landfillsprojects,WaterReservoirsandmorethan100PondLiningprojectsonTurnkey(Supply&Installation)basis,whichincludes Industries, Associations, Mega Projects, Infrastructure projects, ConstructionCompanies,MunicipalCorporations,PSUs,Privatecompaniesetc.

Profile of Institutional Member of Indian Chapter

ABOUT JOURNAL - Geosynthetica · 2020-05-04 · ABOUT JOURNAL Geosynthetics are now being...

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