高性能混凝土自收缩测试方法探讨

8120052JOURNALOFBUILDINGMATERIALSVol.8,No.1Feb.,2005:2003-12-03;:2004-11-05:(59938170):(1973-),,,,.:1007-9629(2005)01-0082-081,2,1,2,2(1.,210096;2.,210008):,;,,,,.:;;;;;:TU528:AStudyontheMeasurementofAutogenousShrinkageofHighPerformanceConcreteTIANQian1,2,SUNWei1,MIAOChang2wen2,LIUJia2ping2(1.DepartmentofMaterialsScienceandEngineering,SoutheastUniversity,Nanjing210096,China;2.JiangsuResearchInstituteofBuildingScienceCo.,Ltd.,Nanjing210008,China)Abstract:Basedonthereviewoftherelativeliteratures,thediscriminationaswellastherelationofthedefi2nitionsbetweentheautogenousshrinkage,self2desiccationshrinkageandchemicalshrinkageoftheconcretewerediscussedfromthepointofviewoftheirdefinitions.Anautomaticautogenousshrinkagemeasuringsystemwasdeveloped,whichadoptedthecombinationofnon2contactsensoraswellasmicrometerandperpendicularaswellashorizontalmeasurementinthedifferentstagesofthestructureevolutionofconcrete.Themeasure2mentcanbestartaftercasting.Themeasuredresultsareconsistentwiththedefinitionandtherepeatedmea2surementsagreeverywell.Keywords:highperformanceconcrete;autogenousshrinkage;self2desiccationshrinkage;chemicalshrink2age;definition;measurement2080,.,[1]..,,,.2000RILEMShrinkageofConcreteShrink2age2000[2],.,,.,.Barcelo[3],.,.,.11.1,.20,LeChatelier[4](absolutevolumechange)(apparentvol2umechange),.Lynam[5],.(JapaneseConcreteInstitute,JCI)[6],.,.,.,.RILEMTC181-EAS[7],,(autogenousshrinkage)(self2desiccationshrinkage):(1),(chemicalshrinkage),.(),.(2),,.,.,,.(3),(settingshrinkage)..(4).[810],,,.1.2,,:(1)(autogenousshrinkage)(apparent)(),().(2)(chemicalshrinkage)(absolute)().(3)(settlementshrinkage)(),().(4)(self2desiccationshrinkage),,,().().381::(1),,.(2)JCI,.(3)RILEMTC181-EAS,,..(4),..,,,().(5).,;,,.22.1,,.,,.,,,.,.,[11].,.,()[12].,,.,().,,.1.,,.,.,.Bjontegaard(1999),Morioka(1999),Lokborst(1998),Holt&Leivo(1999),Jensen&Hansen(1997)[13](1).,:(1).,LVDT.().(),.,.,,.,,.(LVDT),,,488.,,,.(a)Measuringsystemwithmovableendplates(40mm40mm160mmspecimen,Morioka(1999)(c)Measuringsystemwithhorizontalcast2inbars(unit:mm)(150mm150mm1000mmbeam,Lokborst(1998)(b)Measuringsystemwithflexibletubes(100mm375mmspecimen,Jensen&Hansen(1997)(d)Measuringsystemwithhorizontalcast2inbars(270mm270mm100mmbeam,Holt&Leivo(1999)1Fig.1Measurementsapparatusofconcreteautogenousshrinkageatearlyageinthereferences[13](2)..,.,.,,.Jensen&Hansen1CT1DigitalDilatometer,100mm375mm.,.(3).,1.1,,.(Koenders1997AutogenousDeformationTestingMachine(ADTM),),.,.2.22.2.11d,,2.,:(1)581:2Fig.2Measuringsystemofautogenousshrinkageforearly2ageconcretedesignedbytheauthors1Non2contactsensor;2Polytetrafluoroethleneliner;3Steelmould;4Temperaturesensor;5Marbleplate;6ADtransformer;7Computeracquisitionandanalysissystem,,,,.,.,.,,..,3.,();;,().3,,3,;,.3Fig.3Influenceofthemouldrestrictionandthemeasurementdirectiononinitialself2desiccationshrinkage(2)3mm.98mm,500mm.,..0.5h.1d,100mm100mm515mm:2mm,.0.5h.,:(a),.688,,.(b).(c),.(3)DALLAS,0.0625..multiNCDT300,:1mm,0.2%,0.01%;:-50150,0.02%P(1090).:(a),;(b),;(c).,.,,4(a),(b).4Fig.4Fixationpartofthenon2contactsensor,,,.(4),,,.EXCEL.VBA,.,,.(5),,.,.,(VA),(5(a)).,,VA(1d),5(b).2.2.21d,.,,.,1d.100mm100mm515mm,PVC.,,1d.781:(a)Rehologicalcharacters(mwPmc=0.3,paste)(b)Autogenousshrinkage(mwPmc=0.2,paste)5(VA)Fig.5Effectsofthickeningagent(VA)ontherehologicalcharactersandautogenousshrinkageofcementpaste61dFig.6Measurementoftheautoge2nousshrinkageafter1d,110mm110mm550mm,(6).(202),(605)%.2.2.31010-6-1,t(0.5h)vt(10-6)vt=106[(l0-lt)P498+(Tt-T0)1010-6](1):l0,ltt(mm);T0,Ttt().t(0.5h)Ht(10-6)Ht=106[((l01-lt1+l02-lt2)+215(Tt-T0)1010-6)P480+(Tt-T0)1010-6](2):l01,l02(mm);lt1,lt2t(mm);T0();Ttt().3.315%,3;3115%,215%,2,,.71,AB.,.:,70010-6.,,;.,7Fig.7Autogenousshrinkageofconcretemixturebefore1dwiththemeasuringsystemdesignedbytheauthors888,.AB,.3,,.,:1..,;.2.()().,.3..4..5.,,.6.,:;1d;1d.,,.,.:[1]HOLLANDTC.Useofsilica2fumeconcretetorepairabrasion2erosiondamageontheKiznaDamStillingBasin[A].ProceedingsoftheSec2ondInternationalConferenceonFlyAsh,SilicaFume,SlagandNaturalPozzolansinConcrete(SP-91)[C].Detroit:AmericanConcreteInstitute,1986.841-863.[2]BAROGHEL2BOUNYV,AltcinPC.Preface[A].InternationalRILEMWorkshoponShrinkageofConcreteShrinkage2000[C].Par2is:ThePublishingCompanyofRILEM,2000.1.[3]BARCELOL,BOIVINS,RIGAUDS,etal.Linearvs.volumetricautogenousshrinkagemeasurement:Materialbehaviourorexperimentalartefact[A].ProceedingsoftheSecondInternationalResearchSeminaronSelf2desiccationandItsImportanceinConcreteTechnology[C].Lund:LundInstituteofTechnology,1997.109-125.[4]LeCHATELIERH.Surleschangementsdevolumequiaccompagnentledurcissementdesciments[A].BulletindelaSocitdEncourage2mentpourlIndustrieNationale[C].[sl]:[sn],1900.54-57.[5]LYNAMCG.GrowthandmovementinPortlandcementconcrete[M].London:OxfordUnivPress,1934.26,27.[6]TAZAWA.Autogenousshrinkageofconcrete[M].London:Taylor&FrancisBooksLtd,1999.1-67.[7]BENTURA.Terminologysanddefinitions[A].InternationalRILEMConferenceonEarlyAgeCrackinginCementitiousSystemEAC01[C].Haifa:RILEMTC,2001.13-15.[8],.[M].:,1999.263-281.[9],.[J].,2001,4(2):159