摘要
Reconnaissancereportsandpertinentresearchonseismichazardsshowthatliquefactionisoneofthekeysourcesofdamagetogeotechnicalandstructuralengineeringsystems.Therefore,identifyingsiteliquefactionconditionsplaysanimportantroleinseismichazardmitigation.Oneofthewidelyusedapproachesfordetectingliquefactionisbasedonthetime-frequencyanalysisofgroundmotionrecordings,inwhichshort-timeFouriertransformistypicallyused.Itisknownthatrecordingsatasitewithliquefactionaretheresultofnonlinearresponsesofseismicwavespropagatingintheliquefiedlayersunderneaththesite.Moreover,Fouriertransformisnoteffectiveincharacterizingsuchdynamicfeaturesastime-dependentfrequencyoftherecordingsrootedinnonlinearresponses.Therefore,theaforementionedapproachmaynotbeintrinsicallyeffectiveindetectingliquefaction.AnalternativetotheFourier-basedapproachispresentedinthisstudy,whichproposestime-frequencyanalysisofearthquakegroundmotionrecordingswiththeaidoftheHilbert-Huangtransform(HHT),andoffersjustificationfortheHHTinaddressingtheliquefactionfeaturesshownintherecordings.Thepaperthendefinesthepredominantinstantaneousfrequency(PIF)andintroducesthePIF-relatedmotionfeaturestoidentifyliquefactionconditionsatagivensite.Analysisof29recordeddatasetsatdifferentsiteconditionsshowsthattheproposedapproachiseffectiveindetectingsiteliquefactionincomparisonwithothermethods.
出版日期
2005年02月12日（中国期刊网平台首次上网日期，不代表论文的发表时间）
