简介：ShanghaiislocatedineasternChinaandisbuiltonoverburdensoillayers.ItcanbeseenfromtheMexicoMs=8.1earthquakeonSeptember19,1985andtheHanshinMs=7.4earthquakeonJanuary17,1995thatheavycasualtiesandpropertylosseshaveadirectrelationshipwithoverburdensoillayers.Groundmotionscausedbyearthquakesaresignifieantlyamplifiedwhenpassingthroughthesoillayers.Undertheinfluenceoftheseamplifiedmotions,buildingstructures,whosenaturefrequencyiswithinthefrequencybandofsoilamplificationresponse,willexperiencemoreseveredamagethanthosebuiltonbedrock.Therefore,engineeringseismologistshavepaidconsiderableattentiontheamplificationresponsesintheShanghaioverburdensoillayers.TheamplificationresponsesofsoilandsandlayersinthispaperaregivenbytheML=4.1earthquakeinNantong,JiangsuProvinceonDecember25,2001at31.8°N,120.9°E.Itcanbeseenthattheresponsesofsoilandsandlayersareverydifferent.Thatisimportant.

简介：AccordingtotheChineseGB50011-2001codeandtherecommendedprovisionsofFEMANEHRPandEUROCODE8,byusingshearwavevelocityandboreholedata,thesiteclassificationisevaluatedforatypicalsoftsoilsiteontheYantaiseacoast.Thesiteseismicgroundmotioneffectisanalyzedandtheinfluenceofthecoastalsoilondesigngroundmotionparametersisdiscussed.Theresultsshowthatthebriefsiteclassificationcannotrepresenttherealconditionsofasoftsoilsite;thesoftsoilonthecoasthasaremarkableimpactonthemagnitudeandspectrumofgroundmotionacceleration.Themagnificationonpeakaccelerationisbigger,however,duetothenonlineardeformationofthesoil.Themagnificationisreducednonlinearlywiththeincreaseofinputgroundmotion;thespectrumisbroadenedandthecharacteristicperiodelongatedonthesoftsoilsite.