钢框架结构地震破坏诊断及震后残余能力评价研究

钢框架结构地震破坏诊断及震后残余能力评价研究李小华（重庆大学土木工程学院）邮箱：[e-mail]damageVideo！Earthquake’sImpactonSteelBuildings3Earthquake-inducedLocalDamageinSteelFramesReference:ReportforMEXTspecialprojectforreducingvulnerabilityforurbanmegaearthquakedisasters.110cm/s4Earthquake-inducedLocalDamageinSteelFramesReference:ReportforMEXTspecialprojectforreducingvulnerabilityforurbanmegaearthquakedisasters.BucklingFractureBoltslippage250cm/s5CommonPost-earthquakeInspectionMethodFractureArchitecturalfinishesFireproofing▪Requiringextensivecostsandlabors.▪Takingmuchtime.▪Existingmanyfalse-positiveerrors.Non-destructiveevaluation(NDE)✓Visualexamination✓Ultrasonictesting6RapidPost-earthquakeDamageAssessmentDaysaftermainshockNumberofaftershock2342016KumamotoNationalResearchCouncil(USA)Oneof13grandchallengeproblemsintheresearchforachievingaearthquake-resilientcommunity.7SHMSystemsonSteelBuildings▪Mainlyfocusonstructuralconditionassessmentusingglobalcharacteristics(e.g.,modalfrequencyandmodeshape,andinter-storydriftratio).SHMConfiguredbytheU.S.GeologicalSurveyStructuralhealthmonitoring(SHM)applicationtoearthquakeengineeringtoenablerapidpost-earthquakedamageassessment8InvestigationofGlobalCharacteristicsSource:JiX,FenvesG,KajiwaraK,NakashimaM.Seismicdamagedetectionofafull-scaleshakingtableteststructure.J.ofStruct.Eng.2011;137(6):14-21.➢Full-scaleshakingtabletestsforhigh-risesteelbuilding(E-Defense)Structuralconditionassessmentusingglobalcharacteristics(e.g.,modalinfo.,storydrift,etc)areinsufficientforpost-earthquakedamageassessment.Forperformingstrength-basedsafetyevaluationanddeterminerehabilitationstrategyinarapidandobjectivemanner,localdamageinformationisneeded.9ProposedSensingSystemforDamageDetectionLDT1-028KPVDFsensorNaradaunit▪Dynamicstrainsensing▪Highsensitivity▪Lowcost▪Wide-rangefrequencyFractureBeam-columnconnectionSteelbuildingWirelesspiezoelectricstrainsensingLocalDamageEvaluationMethod:DamageIndex%RRRDId100×-=()()RMSreferenceRMSetargtεεR=ProposedDamageIndexDIDamaged()()RMS_dreferenceRMS_detargtdεεR=UndamagedKurataM.,LiX.,FujitaK.,andYamaguchiM.(2013).“Piezoelectricdynamicstrainmonitoringfordetectinglocalseismicdamageinsteelbuildings.”SmartMaterialsandStructures,22,115002.（2017年日本建築学会奨励賞）LiX.,KurataM.,andNakashimaM.(2015).“Evaluatingdamageextentoffracturedbeamsinsteelmoment-resistingframesusingdynamicstrainresponses.”EarthquakeEngineering&StructuralDynamics,44,563-581LocalDamageEvaluationMethod:DecouplingLiX,KurataM,SuzukiA(2016).“Decouplingalgorithmforevaluatingmultiplebeamdamagesinsteelmoment-resistingframes.”EarthquakeEngineering&StructuralDynamics,46(7),1045-1064.1[()]DIΔDIDI1,11,1,2,1,,22,12,2,2jniijinnnjnnΔDecouplingwithInfluencematrix12LocalDamageEvaluationMethod:TranslationLiX.,KurataM.,andNakashimaM.(2016).“Simplifiedderivationofadamagecurveforseismicallyinducedbeamfractureinsteelmoment-resistingframes.”JournalofStructuralEngineering(ASCE),142(6),04016019.22222113311(())(())4(())(())2(())BDIABDIABDIABDIABDIAClosed-formrelationshipofDIandEI4.4m4mRemovableconnectionSimulateddamageB1B2B3B4B5B6B7B8B9B10B11B12Five-storySteelFrameTestbed13DamagepatternTargetofsimulationReductionofstiffness(%)L1Fractureofwholebottomflange53.4L2Fractureofbottomflangeandone-quarterweb79.4L3Fractureofbottomflangeandhalfweb93.6SimulatedBeamFractureDamage15WirelessStrainSensingSystemShakerAntennaAmplifierNARADAwirelessmoduleBatteryMagnetPlasticcaseVideo!!16TestResults:DecouplingforMultipleDamagesMeasureddirectdamageindexDecoupleddamageindexFailed13.8%Successful-15%ShakerS1S2S3S4S5S6S7S8S9S10S11S12B1(L2)B3(L1)B4(L3)B5(L2)B8(L3)17TestResults:EstimationofDamageExtents✓Comparedwithexpectedreductionofbendingstiffness,thevaluesestimatedfromthelocaldamageevaluationmethodhavedifferencesof7%atthemost.ShakerS1S2S3S4S5S6S7S8S9S10S11S12B1(L2)B3(L1)B4(L3)B5(L2)B8(L3)18ShakeTableTests1,000915880880Unit:mmInput:JMA-KobeDamagelinkFracture12345678-100-80-60-40-200DamageCaseReductionofI(%)N21N22N23N2419DamageEvaluationResultsReductionofbendingstiffnessMax.9%errorBottomflangefractureExactvalue20ResidualCapacityEvaluationSuzukiA,KurataM,LiX,ShimmotoS(2017).“Residualstructuralcapacityevaluationofsteelmoment-resistingframeswithdynamic-strain-basedmodelupdatingmethod.”EarthquakeEngineering&StructuralDynamics,inpress.Max.6%differenceStrainSensingStrategySAC20-storysteelframeMax.Driftunderthe2/50setofSACLosAngelesgroundmotionrecords00.050.10.150.20.251471013161921MaximumstorydriftangleFloorlevelMaximumdriftanglepointsMedian84thpercentileSensingstories22Alocaldamageevaluationframeworkthatisspecificallydesignedforevaluatingdamagetobeam-columnconnectionsinsteelmoment-resistingframesissummarizedinthispresentation.Testresultsconfirmedthatthepresentedframeworkoflocaldamageestimatorandthewirelessstrainsensingsystemwerecapableofquantifyingtheextentofseismicbeamfracturesinsteelframeswithgoodaccuracy.ConclusionsThankyouforkindattention!