engineeringcivil.com http://www.engineeringcivil.com/developmentoflightweightconcrete.html
DevelopmentOfLightWeightConcrete
ByDhawalDesaiIITBombay
ABSTRACTThispaperdealswiththedevelopmentoftwotypesoflightweightconcretetheoneusinglightweightaggregate(Pumicestone)andtheotherwaterfloatingtypeusingAluminiumpowderasanairentrainingagent.Thisalsoshowstheimportanceofwater/cementratioasinfirsttypeofconcreteitrelatestothesmoothnessofthesurfaceandinsecondoneitisamajorfactorwhichcontrolstheexpansionofconcrete.
INTRODUCTION:Lightweightconcretecanbedefinedasatypeofconcretewhichincludesanexpandingagentinitthatincreasesthevolumeofthemixturewhilereducingthedeadweight.Itislighterthantheconventionalconcretewithadrydensityof300kg/m3upto1840kg/m3.Themainspecialtiesoflightweightconcreteareitslowdensityandlowthermalconductivity.
Therearemanytypesoflightweightconcretewhichcanbeproducedeitherbyusinglightweightaggregateorbyusinganairentrainingagent.InthisprojectIhaveworkedoneachoftheabovementionedtypes.Bothofthemarenonstructuralconcrete.
1)ByusingPumicestoneasalightweightaggregate:Pumicestoneisalightweightaggregateoflowspecificgravity.Itisahighlyporousmaterialwithahighwaterabsorptionpercentage.Inthiswedonotusetheconventionalaggregateandreplaceitbythepumicestone.
2)ByusingAluminiumpowderasanairentrainingagent:WaterfloatingaeratedconcreteismadebyintroducingairorgasintoslurrycomposedofPortlandcementandsand,sothatwhenthemixsetsandhardens,uniformcellularstructureisformed.Thusitisamixtureofwater,cementandfinelycrushedsand.WemixfinepowderofAluminiumtotheslurryanditreactswiththecalciumhydroxidepresentinitthusproducinghydrogengas.Thishydrogengaswhencontainedintheslurrymixgivesthecellularstructureandthusmakestheconcretelighterthantheconventionalconcrete.
ADVANTAGE:Lightweightconcreteisofutmostimportancetotheconstructionindustry.Theadvantagesoflightweightconcreteareitsreducedmassandimprovedthermalandsoundinsulationproperties,whilemaintainingadequatestrength.Themarginallyhighercostofthelightweightconcreteisoffsetbysizereductionofstructuralelements,lessreinforcingsteelandreducedvolumeofconcrete,resultinginoverallcostreduction.Thereducedweighthasnumerousadvantagesoneofthemisreduceddemandofenergyduringconstruction.
TYPESOFLIGHTWEIGHTCONCRETE:Usinglightweightaggregates:Thistypeisproducedusinglightweightaggregatesuchasvolcanicrockorexpandedclay.Itcanbeproducedwiththeuseofnaturallyminedlightweightaggregates(bulkdensityintherangeof880kg/m3)ormanmadelightweightaggregateslikeAardeliteorLytag(bulkdensity800kg/m3).
Usingfoamingagents:Thisoneisproducedthroughtheadditionofafoamingagentincementmortar.Thiscreatesafinecementmatrixwhichhasairvoidsthroughoutitsstructure.Aeratedcementmortaris
producedbytheintroductionofagasintocementitiousslurrysothatafterhardeningacellularstructureisformed.
TYPESOFLIGHTWEIGHTAGGREGATE:Lightweightaggregatesusedinstructurallightweightconcretearetypicallyexpandedshale,clayorslatematerialsthathavebeenfiredinarotarykilntodevelopaporousstructure.Otherproductssuchasaircooledblastfurnaceslagarealsoused.Alsotherearesomenonstructurallightweightaggregateswithlowerdensitymadewithotheraggregatematerialsandhigherairvoidsinthecementpastematrix.Thesearetypicallyusedfortheirinsulationproperties.
Naturalaggregates:InorganicNaturalAggregates:Diatomite,pumice,scoriaandvolcaniccindersarenatural,porousvolcanicrockswithabulkdensityof500800kg/m3whichmakeagoodinsulatingconcrete
OrganicNaturalAggregates:Woodchipsandstrawcanbemixedwithabindertoprovidealightweightnaturalaggregate.Thesearecellularmaterialswhichhaveairtrappedwithintheirstructuresoncetheyhavelowmoisturecontent.
Manufacturedaggregates:1.Bloatedclay,sinteredflyashandfoamedblastfurnaceslag.2.Lightweightexpandedclayaggregate:Thisisproducedbyheatingclaytoatemperatureof10001200oC,whichcausesittoexpandduetotheinternalgenerationofgasesthataretrappedinside.Theporousstructurewhichformsisretainedoncoolingsothatthespecificgravityismuchlowerthanwhatwasbeforeheatingit.
Foamingagents:Therearesomefoamingagentswhichwhenaddedtothecementslurryformsairvoidsthroughoutitsstructure.Alsotherearesomeagentswhoreactwiththechemicalspresentinthecementslurryandevolvegaseswhichresultsintheexpansionoftheslurryandwhenithardens,leavesairvoidsintheconcretethusmakingitlighterthanthenormalconcrete.
Thebulkdensityoffinelightweightaggregatesisaround1200kg/m3.Thebulkdensityofcoarselightweightaggregatesisaround960kg/m3.
GENERALPROPERTIES:LightWeight:Densityrangefrom650Kg/m3to1850Kg/m3ascomparedto1800Kg/m3to2400Kg/m3forconventionalbrickandconcreterespectively.Despitemillionsoftinyairfilledcells,itisstronganddurable.ThereisLightweightadvantageforthestructuredesign,leadingtosavingsinsupportingstructuresandfoundation.
CompressiveStrength:2.0to7.0N/mm2.
ExcellentAcousticPerformance:Itcanbeusedaseffectivesoundbarrierandforacousticsolutions.Hence,highlysuitableforpartitionwalls,floorscreens/roofingandpanelmaterialinauditoriums.
EarthquakeResistant:Sincelighterthanconcrete&brick,thelightnessofthematerialincreasesresistanceagainstearthquake.
Insulation:Superiorthermalinsulationpropertiescomparedtothatofconventionalbrickandconcrete,soreducestheheatingandcoolingexpenses.Inbuildings,lightweightconcretewillproduceahigherfireratedstructure.
Workability:Productsmadefromlightweightconcretearelightweight,makingthemeasytoplaceusingless
skilledlabour.Thebrickscanbesawed,drilledandshapedlikewoodusingstandardhandtools,regularscrewsandnails.Itissimplerthanbrickorconcrete.
Lifespan:Weatherproof,termiteresistantandfireproof.
SavingsinMaterial:Reducesdeadweightoffillerwallsinframedstructuresbymorethan50%ascomparedtobrickworkresultinginsubstantialsavings.Duetothebiggeranduniformshapeofblocks,thereisasavinginbedmortarandplasterthickness.Inmostcasesthehighercostofthelightweightconcreteisoffsetbyareductionofstructuralelements,lessreinforcingsteelandreducedvolumeofconcrete.
WaterAbsorption:Closedcellularstructuresandhencehavelowerwaterabsorption.
SkimCoating:Donotrequireplasterandwaterrepellentpaintsuffices.Wallpapersandplasterscanalsobeapplieddirectlytothesurface.
ModulusofElasticity:Themodulusofelasticityoftheconcretewithlightweightaggregatesislower,0.50.75tothatofthenormalconcrete.Thereforemoredeflectionisthereinlightweightconcrete.
MANUFACTURING:Itisproducedbyincludinglargequantitiesofairintheaggregate,matrixorinbetweentheaggregateparticlesorbyacombinationoftheseprocesses.Lightweightaggregatesrequirewettingpriortousetoachieveahighdegreeofsaturation.Iftheaggregatesarentfullysaturatedtheyhaveatendencytofloattowardsthesurfaceofthemixafterithasbeenplaced.
Duetothehighermoisturecontentoflightweightconcrete,dryingtimesaretypicallylongerthanregularconcrete.Typically,a0.5watertocementratioslurryisusedasabasemixtureforlightweightconcrete.Thewatercementratiovariesaccordingtospecificprojectrequirements.
Notethatlightweightconcreteobtainsitsnaturalfluidityfromtheairbubblestructure,notfromexcesswatercontent.
EffectofaddingFlyash:Flyashaddedtothecementdoesnotadverselyaffectthebasichardenedstateoflightweightconcrete.Infusingandsupportingthelightweightconcretewiththeaircellsystemisamechanicalactionandisnotproblematicwithflyashorotheradditives.NotethatsomeflyashmixesmaytakelongertosetthanpurePortlandcementapplications.
USES:Theprimaryuseoflightweightconcreteistoreducethedeadloadofaconcretestructurewhichthenallowsthestructuraldesignertoreducethesizeofcolumns,footingandotherloadbearingelements.Sothemarginallyhighercostofthelightweightconcreteisoffsetbythesizereductionofstructuralelements,lessreinforcingsteelandreducedvolumeofconcrete,thusresultinginloweroverallcost.
Theycanalsobeusedforfireprotection,wheretheycanshieldstructuralsteelfromfire.Theyarealsousedasaninsulatingblock.
Lightweightconcretehasbeenusedtoconstructextremelylargecantilevers,asthemembercanbenarrowerduetothedecreaseddeadload.Usingconcreteofalowerdensityresultsinalowerdeadloadandcanresultinsavingsduetosmallermembersizes.Occasionallythiscanallowconstructionongroundwithalowloadbearingcapacity.
Theporosityoflightweightaggregateprovidesasourceofwaterforinternalcuringoftheconcretethatprovidescontinuedenhancementofconcretestrengthanddurability,butthisdoesnotpreventtheneedforexternalcuring.
Structurallightweightconcretehasbeenusedforbridgedecks,piersandbeams,slabsandwallelements
inconcreteandsteelbuildings,parkingstructures,tiltupwalls,toppingslabsandcompositeslabsonmetaldecking.
Note:Theconcretecovertoreinforcementusinglightweightaggregatesinconcreteshouldbeadequate.Usuallyitis25mmmorethanthatofnormalconcretebecauseofitsincreasedpermeabilityandalsoconcretecarbonatesrapidlybywhichtheprotectiontothesteelbythealkalinelimeislost.
AUTOCLAVEDAERATEDCONCRETEUSINGALUMINIUMPOWDER(AAC)AutoclavedAeratedConcrete(AAC)orAutoclavedLightweightConcrete(ALC)isaprecastconstructionmaterialthatismadefromavarietyofaggregatepartsnolargerthansand.Atroughlyonefifthoftheweightofnormalconcrete,itisanincrediblylightweightbuildingmaterial.Itprovidesexcellentthermalandacousticresistanceandalsoprotectsagainsthouseholdhazardsastermitesandfire.AACiscommonlyreferredtoasautoclavedcellularconcretebecausehydrogenbubblesformduringtheproductionprocess,resultinginsmallpocketsofairwithintheconcretethatsubstantiallyincreasethevolumeofthefinalconcreteproduct.Thoughtheprecisecompositionofautoclavedaeratedconcretemayvary,itisgenerallymadeupofquartzsandorsomeotherfineaggregate,cementandwaterorsomeotherbindingcomponentandaluminiumpowder.Thealuminiumpowderreactswiththecementandformshydrogenbubblestoformwithinthemix,therebyincreasingthevolumetoweightratiooftheconcretemix.Afterthemixiscastintothedesiredformandthevolumeincreasingchemicalreactionsoccur,theconcretemix,whichisstillsoft,isautoclaved.
MANUFACTURINGPROCESS:Therawmaterialsarebatchedbyweightanddeliveredtothemixer.Measuredamountsofwaterandexpansiveagentareaddedtothemixerandthecementitiousslurryismixed.
SteelmouldsarepreparedtoreceivethefreshAAC.IfreinforcedAACpanelsaretobeproduced,steelreinforcingcagesaresecuredwithinthemoulds.Aftermixing,theslurryispouredintothemoulds.Theexpansiveagentcreatessmall,finelydispersedvoidsinthefreshmixture,whichincreasesthevolumebyabout50percentinthemouldswithinthreehours.
Withinafewhoursaftercasting,theinitialhydrationofcementitiouscompoundsintheAACgivesitsufficientstrengthtoholditsshapeandsupportitsownweight.Aftercutting,theaeratedconcreteproductistransportedtoalargeautoclave,wherethecuringprocessiscompleted.Autoclavingisrequiredtoachievethedesiredstructuralpropertiesanddimensionalstability.Theprocesstakesabouteightto12hoursunderapressureofabout174psi(12Bars)andatemperatureofabout180oC.
TECHNICALSPECIFICATIONS:Density:300to1600kgpercumthisislightenoughtofloatinwaterCompressivestrength:300to900psiAllowableshearstress:8to22psiThermalresistance:0.8to1.25perin.ofthicknessSoundTransmissionClass(STC):40for4in.thickness45for8in.thickness
TECHNICALPERFORMANCE:FireResistance:Autoclavedaeratedconcreteprovidesthehighestsecurityagainstfireandmeetsthemoststringentfiresafetyrequirements.Duetoitspurelymineralcomposition,AACisclassifiedasanoncombustiblebuildingmaterial.Itisbothresistanttofireupto1200oCandheatresistant.
StructuralPerformance:Autoclavedaeratedconcreteisstronganddurabledespiteitslightweight.AACssoliditycomesfromthecalciumsilicatethatenclosesitsmillionsofairporesandfromtheprocessofcuringinapressurizedsteamchamber,anautoclave.Itsexcellentmechanicalpropertiesmakeittheconstructionmaterialofchoiceforearthquakezones.
SoundInsulation:AAChasexcellentsoundinsulationpropertiescomparedtootherbuildingmaterialswiththesameweight.
Durability:Itretainsitspropertiesfortheentirelifeofabuildingandcanresistwind,earthquake,rain(alsoacidrain),stormandawiderangeofexternaltemperatures.
ADVANTAGES:Ithasbeenrefinedintoahighlythermallyinsulatingconcretebasedmaterialusedforbothinternalandexternalconstruction.BesidesAACsinsulatingcapability,oneofitsadvantagesinconstructionisitsquickandeasyinstallation,forthematerialcanberouted,sandedandcuttosizeonsiteusingstandardcarbonsteelbandsaws,handsawsanddrills.
SustainableConstructionThechoiceoftherightbuildingmaterialisoneofthekeyfactorsforsustainablebuildings.AACisabuildingmaterialwhichoffersconsiderableadvantagesoverotherconstructionmaterials.Itshighresourceefficiencygiveslowenvironmentalimpactinallphasesofitslifecycle,fromtheprocessingofrawmaterialstothedisposalofAACwaste.
EnvironmentalPerformance:Resources:AACismadefromnaturallyoccurringmaterialsthatarefoundinabundancelime,finesand,othersiliceousmaterials,waterandasmallamountofaluminiumpowder(manufacturedfromabyproductofaluminium).FurthermoretheproductionofAACdemandsrelativelysmallamountsofrawmaterialsperm3ofproduct,anduptoafifthasmuchasotherconstructionproducts.
Environmentalimpactduringproduction:Norawmaterialsarewastedintheproductionprocessandallproductionoffcutsisfedbackintotheproductioncircuit.ThemanufactureofAACrequireslessenergythanforallothermasonryproducts,therebyreducinguseoffossilfuelsandassociatedemissionsofcarbondioxide(CO2).Industrialqualitywaterisusedandneitherwaternorsteamisreleasedintotheenvironment.Notoxicgasesarecreatedintheproductionprocess.
Environmentalimpactduringuse:AACsexcellentthermalefficiencymakesamajorcontributiontoenvironmentalprotectionbysharplyreducingtheneedforspaceheatingandcoolinginbuildings.
Inaddition,AACseasyworkabilityallowsaccuratecuttingthatminimizesthegenerationofsolidwasteduringuse.ThefactthatAACisuptofivetimeslighterthanconcreteleadstosignificantreductionsinCO2emissionsduringtransportation.
Reuse,recoveryanddisposal:ThroughoutthelifecycleofAAC,potentialwasteisreusedorrecycledwhereverpossibletominimizefinaldisposalinlandfill.WhereAACwasteissenttolandfill,itsenvironmentalimpactisminorsinceitcontainsnotoxicsubstances.
DISADVANTAGES:Autoclavedaeratedconcreteisnotwithoutitsdisadvantages.Forexample,itisnotasstrongaslessporousvarietiesofconcrete,soitmustoftenbereinforcedifitistobeusedforintenseloadbearingwork.Thoughitcanbeshippedjustaboutanywherewithrelativeeasebecauseofitslightweight,autoclavedaeratedconcreteisnotwidelyproduced,soitmaybedifficultformanytoobtainitlocally.Itmustalsobecoatedwithsomeformofprotectivematerial,asittendstodegradeovertimebecauseofitsporousnature.
USES:Itisalightweight,precastbuildingmaterialthatsimultaneouslyprovidesstructure,insulation,andfireandmouldresistance.AACproductsincludeblocks,wallpanels,floorandroofpanelsandlintels.
USEOFALUMINIUMPOWDER:Thereactantsinaeratedconcretearelime(whichispresentincement)andaluminiumpowder.Whenthe
aluminiumpowderisaddedtoslurryoflime,hydrogenisproducedintheformofbubbles.Thickslurryismadewithlime/cementalongwithaggregates.Aluminiumpowderisaddedinthefinalstageofmixing.Themixispouredintomoulds.Themouldsareautoclavedwhichimpartsstrength.AACisproducedusingnoaggregatelargerthansand.
Quartzsand,limeand/orcementandwaterareusedasabindingagent.Aluminiumpowderisusedatarateof0.05%0.08%byvolumeofcement.
Thehydrogengasfoamsanddoublesthevolumeoftherawmix(creatinggasbubblesupto1/8inchindiameter).Attheendofthefoamingprocess,thehydrogenescapesintotheatmosphereandisreplacedbyair.Dependingonitsdensity,upto80%ofthevolumeofanAACblockisair.AACslowdensityalsoaccountsforitslowstructuralcompressionstrength.Itcancarryloadsupto1,200Psi,approximatelyonlyabout10%ofthecompressivestrengthofregularconcrete.
AACmaterialcanbecoatedwithastuccocompoundorplasteragainsttheelements.SidingmaterialssuchasbrickorvinylsidingcanalsobeusedtocovertheoutsideofAACmaterials.
EXPERIMENTSOFAAC:SincetheautoclavefacilitywasunavailableattheplacewhereIwasworking,Ididnotautoclavemysamplesandthuswasunabletofinditsactualstrength.
Themixdesignforthefirstsamplewasdecidedbasedonstudies.Thenfurthersamplesweremadebychangingsomeproportionsinthepreviousones.
Sampleno.1:Inthisthecement/sandratiotakenis1:1.Alsothew/cmratiotakenis0.4.Aluminiumpowderis0.40.5%byweightofcement.
Cement(OPC):1.08kgSand:1.08kgWater:440gmAluminiumpowder:45gm
Themixturewashotjustaftermixingwhichconfirmedthechemicalreactioninthat.Alsohissingsoundwascomingwhichconfirmedtheevolutionofgas.Sincethisisaeratedconcrete,itshouldexpand.Butitdidnot.Thereasonwaslessamountofwatersinceitdidnotformslurryandthereweregapsbetweentheparticlesthroughwhichalltheevolvedgasesescapedoutfromtheconcrete.Thesegasesshouldremainthereonlysothattheconcreteexpandsbutitdidnothappen.
Soforthenextsample,Iincreasedthew/cmratiotomaketheslurry.Sampleno.2:Withw/cmratio=0.45Cement(OPC):540gmSand:540gmWater:243gmAluminiumpowder:3gm
Thismixturemadeslurrywhichwaseasilyflowing.Inthisjustafterfillingthecubetheinitialdepthofthetopsurfaceoftheslurrywas11.5cm.Afterjust5minutes,thedepthwas10cmwhichshowedthatitexpandedaswepredicted.
Weightofthesample:1.14kgVolume:15x15x5cm3
Density:1013.33kg/m3
Sampleno.3:Toreducedensityfurther,Idecreasedthequantityofsand.Cement(PPC):1080gmSand:940gmWater:490gmAluminiumpowder:6gm
Inthissampletheinitialdepthofthetopsurfaceoftheslurrywas6.8cmandjustafter5minutesthedepthwas3cm.
Weightofthesample:2.02kgVolume:15x15x12cm3
Density:748.15kg/m3Thiswasfloatinginwater.
Sampleno.4:InthisnewsampleItriedtousePumiceStonepowderandreducedthequantityofsandinthemixture.InthissampleIhadtousemorequantityofwatersincepumicestoneabsorbswater.Cement(PPC):1080gmSand:840gmPumiceStonePowder:120gmWater:660gmAluminiumpowder:6gm
Inthissampletheinitialdepthofthetopsurfaceoftheslurrywas8.6cmandthefinaldepthwas4.5cm.
Weightofthesample:2.04kgVolumeofthesample:15x15x10.5cm3
Density:863.49kg/m3
Sampleno.5:Sampleof2cubes.Cement:16202=3240gmSand:12602=2520gmPumicestonepowder:1802=360gmWater:9252=1850gmAluminiumpowder:92=18gm
Sampleno.6:Sampleof2cubes
Cement:12962=2592gmSand:10082=2016gmPumicestonepowder:1442=288gmWater:7402=1480gmAluminiumpowder:72=14gm
Heretheinitialdepthoftopsurfaceofboththecubeswas6cmandthefinaldepthwas0cm.
Weightofeachcube:2.45kgVolumeofeachcube:15x15x15cm3
Density:725.92kg/m3
Soinall,samplenumbers3,4,5and6werethesuccessfulones.Theyallwerefloatinginwater.
LIGHTWEIGHTCONCRETEUSINGPUMICESTONE:ThewordPumiceisageneraltermusedforarangeofporousmaterialsproducedduringvolcaniceruptions.Pumicestonecanbeweakandporousorstrongandlessporous.Itswaterabsorptionisashighas55%sinceitisahighlyporousmaterial.Themajorreasonbehindusingpumiceasanaggregateisitsmuchlightweightandcomparativelyhighstrength.
Pumicestone:light,spongy,highlyporouskindoflavawithavitreoustexture.Pumicehashighsilica&alkaliandlowcalcium&magnesiacontent.Itsspongycellulartextureisaresultofthegasesescapingfromhot
lava.Itishavinglowstrengthanditisagoodthermalinsulator,soundinsulatorandfireinsulator.
TESTSONLIGHTWEIGHTCONCRETEUSINGPUMICESTONEASALIGHTWEIGHTAGGREGATE:Forthisproject,wegotpumicestoneasbigas50mmsize.Sowecrushedittothesizelessthan20mm.Themixdesignforthefirstsamplewasdecidedbasedonstudies.Thenfurthersamplesweremadebychangingsomeproportionsinthepreviousones.
Sampleno.1:1cubeCement:1.18kgSand:2.63kgPumice:(>10mm):590gm(4.7510mm):910gm(10mm):600gm(4.7510mm):430gm(
TheadmixtureusedwasSikaViscocrete5001.Thismadewaterreleasefromcementparticles.
Afteropeningitwefoundthatitsfinishwasnotgood.Someareasweresmoothandsomewerenot.Itsreasoncameouttobethelargerparticlesofpumicestone.SonexttimeIdidnotuseparticlesbiggerthan10mm.
Sampleno.3:for3cubesusingaggregateslessthan10mm.Cement:3540gmSand:1800gmPumice(smallerthan10mm):4100gmWater:3400gmAdmixture:21gm
Thesecubeshadlowdensityandalsosmoothsurface.
7dayscubetesting:
S.no,Weightofcube(Kg),Density(Kg/m3),Load(kN)Strength(MPa)1,4.2,1244.44,163.0,7.242,4.4,1303.70,148.4,6.60
Sampleno.4:Samplefor2cubes.Cement:3540gmSand:2100gmPumice:(4.7510mm):2180gm(
architecturalconcrete.Itisagoodinsulatorofheatandsoundandthushasthesameusesasoftheaboveaeratedconcrete.
REFERENCES1)AmbujaKnowledgeCentreLibrary.AmbujaCementsLtd.2)SamuelGreen,NicholasBrookeandLenMcSaveney.Pumiceaggregateforstructurallightweightandinternallycuredconcretes3)Keertana.B,SiniSaraManiandM.Thenmozhi.Utilizationofecosandandflyashinaeratedconcreteforarichestmixdesign4)HjhKamsiahMohd.Ismail,MohamadShazliFathiandNorpadzlihatunbteManaf.Studyoflightweightconcretebehavior5)HandbookonaeratedconcreteproductsbyPTYLtd6)GiuseppeCampioneandLidiaLaMendola.Behaviorincompressionoflightweightfibrereinforcedconcreteconfinedwithtransversesteelreinforcement(2002)
ACKOWLEDGEMENTI,DhawalDesai,2ndyearundergraduatestudentofCivilEngineeringdepartment,IndianInstituteofTechnologyBombay,gratefullyacknowledgethesupportandlabfacilityprovidedbyM/sAmbujaCementsLtd.Mumbai,tocarryoutthisprojectworkonLightweightConcreteduringmyinternshipinDec,2011wintervacation.
Weatengineeringcivil.comarethankfultoErDhawalDesaiforsubmittinghispaperonDevelopmentOfLightWeightConcretetous.Wearehopefulthiswillbeofgreatusetoallthosewhowishtoknowmoreaboutthistopic.