摘要
Aone-dimensionalequivalentlinearmethod(EQL)iswidelyusedinestimatingseismicgroundresponse.Forthismethod,theshearmodulusanddampingratioofinelasticsoilaresupposedtobefrequencyindependent.However,historicalearthquakerecordsandlaboratorytestresultsindicatethatnonlinearsoilbehaviorisfrequencydependent.Severalfrequency-dependentequivalentlinearmethods(FDEQL)relatedtotheFourieramplitudeofshearstraintimehistoryhavebeendevelopedtotakeintoaccountthefrequency-dependentsoilbehavior.Furthermore,theshearstrainthresholdplaysanimportantroleinsoilbehavior.Forshearstrainsbelowtheelasticshearstrainthreshold,soilbehavesessentiallyasalinearelasticmaterial.Toconsidertheeffectofelastic-shear-strain-thresholdandfrequency-dependentsoilbehavioronwavepropagation,theshear-strain-threshold-andfrequency-dependentequivalentlinearmethod(TFDEQL)isproposed.AseriesofanalysesisimplementedforEQL,FDEQL,andTFDEQLmethods.Resultsshowthatelastic-shear-strain-thresholdandfrequency-dependentsoilbehaviorplaysagreatinfluenceonthecomputedsiteresponse,especiallyforthehighfrequencyband.Also,theeffectofelastic-strain-thresholdandfrequency-dependentsoilbehavioronthesiteresponseisanalyzedfromrelativelyweaktostronginputmotion,andresultsshowthattheeffectismorepronouncedasinputmotiongoesfromweaktostrong.
出版日期
2014年06月16日(中国期刊网平台首次上网日期,不代表论文的发表时间)