experimental investigation of hydration of ternary blended cement paste

1、ExperimentalinvestigationofhydrationofternaryblendedcementpasteZhijunTan1GuangYe12YunGao3LievenMachiels4ElsBruneel5GeertDeSchutter11MagnelLabatyfConcreteResearchGhentUniversityBelgium2MicrolabFacultyofCivilEngineeringGeo

2、sciencesDelftUniversityofTechnologytheherls3DepartmentofMaterialScienceEngineeringSoutheastUniversityP.R.China4CentrefHighTemperatureProcessesSustainableMaterialsManagementDepartmentMetallurgyMaterialsEngineeringKULeuven

3、LeuvenBelgium5DepartmentofInganicPhysicalChemistryGhentUniversityBelgiumAbstractInthispaperternarybinaryblendedcementpastesaswellaspurePtlcementpastewerepreparedbyPtlcementgroundgranulatedblastfurnaceslag(GGBFS)limestone

4、powderwaterwhichwerethenhydratedfrom1to91daysat20Cinasealedenvironment.AteachcuringagethehydrationkiicsofcementslagwasdeterminedbyXRDRietveldivedissolutionmethod(EDTA)respectively.ThecontentofCaCO3(limestone)wasquantifie

5、dbyThermogravimetricanalysis(TGA)technique.Thedegreeofhydrationofcementclinkerwasdistinctlyacceleratedbythesingleadditionofslaglimestonewithin91daysofhydration.Thecoexistenceofslaglimestoneinternaryblendedcementaccelerat

6、edthehydrationofcementclinkerwithinthefirst14daysofhydrationbutloweredthedegreeofhydrationofcementclinkerafter91daysofhydrationcomparedwithotherpastes.Thedegreeofreactionofslaginblendedcementpasteswasabout8%35%after191da

7、ysofhydrationrespectivelywhichwasalmostnotinfluencedbytheadditionoflimestonepowder.Asmallamountoflimestonei.e.around2%ofthetotalsolidrawmaterialswasreactedinpastesmainlyoccurredattheearlyage.Basedontheexperimentalinvesti

8、gationtheresultsshowthatthehydrationofcalciumsilicatephasesofcementinpasteswasenhancedbythepresenceoflimestonebuthamperedbyslag.Thehydrationofcalciumaluminaphasesofcementwasgreatlyacceleratedbytheadditionofslagalsoenhanc

9、edbythepresenceoflimestonepowderinbinaryblendedlimestonecementpasteatearlyage.Howeverthecoexistenceoflimestonewithslaginternaryblendedcementpasterestrainedthehydrationofcalciumaluminaphasesofcement.iginalityThehydrationp

10、rocessofblendedcementpasteisofsignificantimptancelikeitisfpurePtlcement.Limitedwkhasbeenperfmedonternaryblendedcementpastesduetocomplexityofternaryblendedsystemsaswellasthelackofadvancedexperimentaltechniques.Basedonaser

11、iesofexperimentalproceduresthispaperexperimentallyinvestigatedthehydrationkiicsofternaryblendedcementpastesaswellasthecrespondingreferencepastes.Thepaperpresentstheresultsshowstheinfluenceofeachmaterialontheothersinthete

12、rnaryblendedcementpastesystematicallycomparedwiththerelevantreferences.Theresultshelpunderstthehydrationbehaviofternaryblendedcementpastewhichbenefitstheresearchonmodelingofternaryblendedcementpaste.Keywds:Ternaryblended

13、cementSlagKiicsLimestonePtlcement1.IntroductionIntermsofthetendenciesinthemoderncementindustrythemostimptantarethoseconnectedwitheconomicalecologicalfacts.OverthelastdecadesSupplementaryCementitiousMaterials(SCMs)suchasf

14、lyashsilicafumeblastfurnaceslaghavebeenwidelyusedinconstructionindustryalloverthewldbecausetheuseofSCMsbringsseveraladvantagesoverPtlcement.FirstlythecostofSCMsischeaperthanPtlcementastheyareusuallybyproductsofindustry.S

15、econdlytheproductionofSCMsconsumeslessenergyreducesCO2emissioncomparedtothat1Crespondingauth:Tel3292645521Fax3292645838Figure1Particlesizedistributionofrawmaterials.2.Experiments2.1.RawmaterialsThreematerialsi.e.Ptlcemen

16、t(Pinsht)grgranulatedBlastfurnaceslag(B)Limestonepower(L)werechosenastherawmaterialsinthisresearch.dinaryPtlcement(OPC)wasCEMI52.5complyingwiththeEuropeanstardEN1971(2000)(EN19712000).SlagwasofferedbyCEMcompanywithahydra

17、ulicmodulus(CAMS)1.66whichishigherthantheminimum1.0accdingtoGermanspecification(H.F.W.Tayl1997).Limestonepowderwasproducedfromcarboniferouslimestonewithahighpurityof98.3%CaCO3(bymass)quantifiedbyTGAtechnique.Thechemicalc

18、ompositionsofcementlimestonepowderslagarelistedinTable1.Fig.1showsthecumulativeparticlesizedistribution(PSD)curvesofthethreematerialsmeasuredbylaserdiffractionmethod.2.2.MixdesignofpastesIndertohavereferencesofneatPtlcem

19、entbinaryblendedcementsfourgroupsofpastesweredesignedasfollows:1.PC:100wt%Ptlcement.2.PL:10wt%limestonepowderblendswith90wt%Ptlcement.3.PB:30wt%Ptlcementblendswith70wt%slag.4.PBL:10wt%limestone60wt%slagblendedwith30wty%P

20、tlcement.Thewatertopowderratio(wp)ofthefourgroupsofmixeswasconstantlyfixedat0.40i.e.1.00gsolidmaterial(s)wasmixedwith0.40gwater.ThemixingprocedurewastakenfromEuropeanstardEN1961:2005withtheconsiderationoftheadditionofsla

21、glimestone.Firstslaglimestonepowderwerewasaddedmixedatlowspeedftwominutestowelldispersetheslaglimestonepowderincement.LaterthemixingprocedurewasstrictlycarriedoutasdescribedinEN1961:2005.Feachsamplethewellmixedpastewasca

22、stinasealedplasticcylinderbottlewithavolumeof90cm3.Thesealedpastewasrotatedataspeedof2.5revolutionsperminuteinaroomwithtemperature20Cf24hourstoavoidbleeding.Laterthesamplewascuredatthesametemperaturetilleachduecuringage.