用声发射技术研究水泥基复合材料脆性

,,(,200092):(AE),,Weibull,m,m,:;;;;:TG115.28:A:100026656(2001)1020421203STUDYONTHEBRITTLENESSOFCEMENT2BASEDCOMPOSITEBYACOUSTICEMISSIONTECHNIQUECHENBing,ZHANGDong,YAOWu(StateKeyLaboratoryofConcreteMaterialResearch,TongjiUniversity,Shanghai200092,China)Abstract:Theacousticemission(AE)characteristicsofthethree2point2bendingconcretebeamsofdifferentkindsofcon2creteswereinvestigatedduringtheentireloadingperiod.ItwasfoundthatthefiberintheconcreteinfluencedtheAEcharacteris2ticssignificantly.Withfibersintheconcrete,theoccurrenceofAEeventsdecreasedobviously.WeibullfunctionwasadoptedtoanalyzetheinfluenceofmaterialpropertiesontheAEcharacteristics,thefracturecharacteristicsandbrittlenessofconcretequanti2tatively.Itwasalsorevealedthatthetwoparametersandmhadspecialmeanings.andmindicatedthebrittlenessdeterminedbythegeometriesofconcretespecimensandmaterialpropertiesrespectively.Keywords:Acousticemission;Concretebeam;Brittleness;Fracturecharacter;Composite,[1],AE,,HMihashi[2];[3],;HLChen[4],:2000210208,,,1,PhysicalAcousticCorporationSPARTANAT2000150kHz(1)(40dB)1242310200110NDTVol.23No.10Oct.2001©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.1,,10cm,10cm10cm51.5cm(1),28d,,5cm(),,111)Pkgm-3%116826711574011101.2521682671157401110701.33168267115740111021.3:1)1.2.3.22.1,0.025mmPmin2(2)2,,,,,2222,,80%2,285%95%pmax(pmax),;,,,,2.2,(),,Weibull,,,f()=m(-0)m-1exp[-(-0)m]224:©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.,m0,,F()=0f()d=1-exp[-(-0)m],,,()dNPdNtot,f()=dNdNtotNF()=NNtot,Weibull,()99.5%3AEWeibull;Weibull2;Weibull,Weibull,f()=dNdNtot=m(-0)m-1exp[-(-0)m]F()=NNtot=1-exp[-(-0)m]02AEWeibullGf2,m,m,;m,,(a)(b)(c)3AEWeibull,;,(457)324:©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.,100,,70%5mm,,,1997,,,,30,,;,19981998,(438)427C25,,,,C25:[1],.[M].:,1992.[2].[J].,1999,21(5):210-219.[3]DavisAllenG.Nondestructiveevaluationofexistingdeepfoundations[J].JournalofPerformanceofConstructedFacil2ities,1995,47(4):57-74.[4]SturrupbyvR,VecchioFJ.[A].[C].:1984.75-87.[5].[M].:,1988.(423)2m0PmmGfPNm-121.501.590.02414521.581.860.0418421.632.040.024315,,,m,AE,;[5],,,m,,Weibullm,m,m,m,,3(1),2,(2)Weibull,m,m,;:[1],.[J].,1997,19(4):6-10.[2]MihashiH,NomuraN,NiisekiS.Influenceofaggregatesizeonfractureprocesszoneofconcretedetectedwiththreedi2mensionalacousticemissiontechnique[J].CementandCon2creteResearch,1991,21(5):737.[3],,.[J].,1995,17(4):25.[4]ChenHL,ChengCT,ChenSE.Determinationoffractureparametersofmortarandconcretebeamsbyusingacousticemission[J].MaterialsEvaluation,1992,50(7):888-894.[5],,.[J].,1998,1(4):315-319.754:©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.