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简介：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.

简介：Thecomputationoftherepresentativegroundmotions,tobeusedasinputforthedynamicanalysesofastruc-tureataparticularsite,canbeapproachedbyseveralmethods.Thechoiceoftheapproachdependsontwofactors:theda-taavailableandthetypeofproblemtobesolved.Thispaperreportstheexperienceoftheauthorsinapproachingaspecificcasestudy:theSouthernMemnonColossus,locatedinLuxor,Egypt.Theresultsareofinterestwhenthehazardanalysisestimationindevelopingcountriesandthesafeguardofculturalheritageareconcerned.Monumentshavetobetreatedasimportantstructures,duetotheirhistoricalandeconomicalvalue.Hence,standardproceduresofprobabilisticseismichaz-ardanalysisfortheseismicclassificationofcommonbuildingshavetobedisregarded.Ontheotherhand,theconsequencesofthecollapseofamonumentarenotcomparabletothoserelatedtostructuressuchasnuclearpowerplantsandlargedams,forwhichthedeterministicseismichazardanalysisprovidesastraightforwardframeworkforevaluationoftheworstcaseone,isadopted.Itsstochasticcomponentcancapturesignificantcharacteristicsofearthquakes,primarilythefrequencycontentswhichdependonthemagnitude(oftenreferredtoastheearthquakescalinglaw).

简介：Atrapezoidvalleysiteischosenasaresearchsite,andaccordingtonumericalmodelsbasedonorthogonaldesign,thefactorsinfluencinggroundmotioninthevalleysitearestudiedwithtwo-dimensionalfinitedifferencemethod.Theinfluencingfactorsareranked,andthenthecalculationresultsareverifiedbygroundmotionanalysis.Theconclusionsareasfollows:therearefourfactorsthathaveimportanteffectsongroundmotionoftrapezoidvalleysites,buttheeffectsaredifferentasthelocationofsiteschanges,theinfluencingfactorsrankdifferentlywithdifferentsitelocations;Therankingoftheinfluencingfactorsisthesameforallthesiteslocatedwithinadistanceof40mfromthevalley'sside,amongthem,themosteffectiveoneisthevalleyslopeangleranks,followedbydepth-to-widthratio,overburdenthickness,atlasttheinputgroundmotionintensity.Theimpactofthefactorsonsurfacegroundmotionisroughlythesameinthevalleysiteswithinacertaindistancetothevalleyside,andthegeometricparametersofthevalleyterrainplayagreaterpartininfluencinggroundmotion.Withtheincreaseofdistanceawayfromthevalley'sside,therankingoftheinfluencingfactorsalsochanges,theratingofslopeanglemovesbackward,therankingoftheinputgroundmotionandoverburdenthicknessmoveahead.Theeffectofvalleygeometricparametersongroundmotionsisgraduallyweakened,buttheeffectofothertwoinfluencefactorsaregraduallyincreased,similartocasesofahorizontallayeredsite.StrongmotionrecordsinAnningRivervalleysitewereanalyzed,andtheresultsshowthatthevalleytopographyhasasignificantamplificationeffectongroundmotion,andthatthenumericalresultsofthispaperarecredible.

简介：Newmarkdesignspectrahavebeenimplementedinmanybuildingcodes,especiallyinbuildingcodesforcriticalstructures.PreviousstudiesshowthatNewmarkdesignspectraexhibitloweramplitudesathighfrequenciesandlargeramplitudesatlowfrequenciesincomparisonwithspectradevelopedbystatisticalmethods.Toresolvethisproblem,thisstudyconsidersthreesuitesofgroundmotionsrecordedatthreetypesofsites.Usingthesegroundmotions,influencesoftheshear-wavevelocity,earthquakemagnitudes,source-to-sitedistancesontheratiosofgroundmotionparametersarestudied,andspectrumamplificationfactorsarestatisticallycalculated.Spectralboundsforcombinationsofthreesitecategoriesandtwocasesofearthquakemagnitudesareestimated.Sitedesignspectrumcoefficientsforthethreesitecategoriesconsideringearthquakemagnitudesareestablished.TheproblemsofNewmarkdesignspectracouldberesolvedbyusingthesitedesignspectrumcoefficientstomodifythespectralvaluesofNewmarkdesignspectraintheaccelerationsensitive,velocitysensitive,anddisplacementsensitiveregions.

简介：如果他们一起被联合调查考古学的地点，渗透雷达，电磁的地面传导性，和电的断层摄影术的地面证明了是有效工具。我们在Akhmim考古学的地点进行了地球物理的调查，我们的调查的主要目的是定位另外的为进一步的挖掘的埋葬的结构。地球物理的数据用GEM-300多频率地面传导性剖析程序，SIR2000地面渗透雷达，和SyscalR2抵抗力米系统在区域被获得。综合解释的结果显示出很多个埋葬的特征和一个强壮的线性地区大约1m宽与一面埋葬的墙的怀疑的趋势与一致。看起来是任何一个方面上的猛烈思考的二条平行山脉，显示二面平行的墙扩大了东方西方，一个房间在底部被识别这个地点的左角落。而且，一些的解释结果选择了GPR和邻近的偶极子偶极子抵抗力侧面露天博物馆在能仍然在沙被埋葬的以前发现的塑像右边建议RamsesII的第二尊塑像的存在。

简介：Basedonthesitehistoricalearthquakedata,amethodofseismicriskanalysisispresented.Oncethefrequencyofearthquakeresponseintensityandtherelativevalueshowedalogarithmiclinear,themaximumsimilaritymethodwouldbeusedtoobtainβ,λ,andImax,andalsoachievetheresultsofriskanalysisoneachsite.Atthesametime,the"logictree"methodcanbeusedtocalibratetheuncertaintyoftheriskoneachsite.Thenthefinalresultsofriskanalysisindicatethatthismethodisfeasible,particularlyforthesitesshowingintensityanomaly.

简介：Accordingtotheresultsofsiteseismichazardanalysisaccomplishedinthepastdecades,96site-relateddesignspectraareselectedassamplesinthisstudy.Theresultshowsthatthevalueofthecornerperiod(Tg)ofthedesignspectruminGBJ11-89(ChinaSeismicBuildingCode,issuedin1989)islowerthanthevalueobtainedbysiteseismichazardanalysis.ThesamesituationexistswhenwecomparethedesignspectraoftheCodestothespectraaccordingtotheearthquakerecords.Thevalueincurrentseismicdesigncode,GBJ50011-2001issuedin2001,isgreaterthanthatinGBJ11-89,butstilllessthanthevalueobtainedbysiteseismichazardanalysis.Ifweacceptthevaluegotbysiteseismichazardanalysis,wehaveasuspicionthat2/3ofbuildingsbuiltaccordingtoGBJ11-89willnotbesafewhenanearthquakewith2%probabilityofexceedancein50yearsoccurs.

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简介：Theseismotectonicmethodisusedtostudytheseismogenicstructuresandthemaximumpotentialearthquakearoundanengineeringsiteinordertodeterminetheseismicriskatthesite.Analysisofseismicriskfromsiteeffectseismicintensitydata,incombinationwithregionalseismo-geologicaldata,usingtheseismotectonicmethodcanprovideamorereliableresult.Inthispaper,takingtheareaofsixreservoirdamsitesinwesternAnhuiasanexample,weanalyzetheseismicriskfromsiteeffectseismicintensitydataincombinationwiththeseismotectonicconditionsandfindthatP(I≥i)=10%over50years.Theresultshowsthattheseismogenicstructureandthemaximumpotentialearthquakehaveacontrollingeffectonseismicriskfromfutureearthquakesintheareaaroundthesite.

简介：喷雾器(n=27)的每日的样品在Fukang从9月21日被收集到2013年10月4日(44.17

简介：Theroleplayedbythediffractionfieldontheproblemofseismicsiteeffectsisstudied.ForthatpurposewesolveandanalyzesimplescatteringproblemsunderPandSVin-planewaveassumptions,usingtwowellknowndirectboundary-element-basednumericalmethods.Afterestablishingthedifferencebetweenscatteredanddiffractedmotions,andintroducingtheconceptofartificiousandphysicallybasedincomingfields,weobtaintheamplitudeoftheFourierspectraforthediffractedpartoftheresponse:thisisachievedafterestablishingtheconnectionbetweenthespatialdistributionofthetransferfunctionoverthestudiedsimpletopographiesandthediffractedfield.Fromthenumericalsimulationsitisobservedthatthisdiffractedpartoftheresponseisresponsiblefortheamplificationofthesurfacegroundmotionsduetothegeometriceffect.Furthermore,itisalsofoundthatthediffractionfieldsetsinafingerprintofthetopographiceffectinthetotalgroundmotions.Theseconclusionsarefurthersupportedbyobservationsinthetime-domainintermsofsnapshotsofthepropagationpatternsoverthecompletecomputationalmodel.Inthissensethegeometricsingularitiesareclearlyidentifiedassourcesofdiffractionandfortheconsideredrangeofdimensionlessfrequenciesitisevidentthatlargeramplificationsareobtainedforthegeometriescontainingalargernumberofdiffractionsourcesthusresultinginastrongertopographiceffect.Theneedforclosed-formsolutionsofcanonicalproblemstoconstructarobustanalysismethodbasedonthediffractionfieldisidentified.

简介：Tianluoshan地点的Paleosalinity记录从泥土矿物质的measurations数据被导出，硼，锶，钡，在在Tianluoshan地点的三侧面的领域采样以后。相对的海水平变化根据实验室结果被讨论。记录显示Tianluoshan地点定位了的区域见证以前高看台的水平至少三次相对的海，在期间并且在Hemudu时期以后。基于以前的研究，这篇论文也集中于包括地讨论Hemudu文化的几个环境元素，在环境状况之间的相互关系，人的活动和开发。

简介：有5.7的大小的地震在Nyingchi区域发生在2003年8月18日，西藏。macroseismic震中高位于unpopulated山区，Zhamo镇的13km南方，Bomi县。在meizoseismal区域的地震紧张是度。and区域分别地是2000km2和11000km2。这个地震事件在NE方向与在NW方向和Zhamo-Maniweng差错trending的Lhari差错trending的运动有关。由于这地震，在区域的大楼糟糕被损坏。

简介：PM2.5喷雾器从2009年4月在城市的Chengdu被取样到2010年1月，并且他们的化学作文为元素详细被描绘，浇可溶的无机的离子，和碳的物质。PM2.5的年度一般水准是165gm3，它通常比另外的中国城市里的大小高，建议城市里的严肃的微粒污染问题。水可溶的离子包括元素的碳和器官的碳贡献了43.5%到年度全部的PM2.5集体、碳的喷雾器贡献了32.0%，并且踪迹元素贡献了13.8%。不同每日、季节的变化在PM2.5和它的部件的集体集中被观察，反映不同人为、生来的来源的季节的变化。对中立粒子弱酸被作出对有利的裁决PM2.5。从来源分配分析识别的PM2.5的主要来源包括了煤燃烧，交通用尽，燃烧的生物资源，土壤灰尘，和构造清扫排出物。低硝酸盐：硫酸盐比率建议静止排出物比车辆排出物更重要。铵硫酸盐的重建的群众，铵硝酸盐，微粒碳的物质，和好土壤说明了79%全部的测量PM2.5质量；他们也说明了散布的92%全部的测量粒子。

简介：ThemaintechnicalbackgroundsandrequirementsareintroducedwithregardtoearthquakegroundmotiondesignparametersinseveraldomesticandAmericanstandards,codesandguidesinvolvedintheseismicanalysisanddesignactivitiesofnuclearpowerplantsinChina.Basedontheresearchresultsfromsiteseismicsafetyevaluationofdomesticnuclearpowerplantprojectsinthelastyears,characteristicsanddifferencesofsitespecificdesignspectraareanalyzedincomparisonwithstandardresponsespectra,andthesuitabilityofstandardresponsespectrafordomesticnuclearpowerplantprojectsisdiscussed.

简介：Buildingcodeshavewidelyconsideredtheshearwavevelocitytomakeareliablesubsoilseismicclassification,basedontheknowledgeofthemechanicalpropertiesofmaterialdepositsdowntobedrock.Thisapproachhaslimitationsbecausegeophysicaldataareoftenveryexpensivetoobtain.Recently,otheralternativeshavebeenproposedbasedonmeasurementsofbackgroundnoiseandestimationoftheH/Vamplificationcurve.However,theuseofthistechniqueneedsaregulatoryframeworkbeforeitcanbecomearealisticsiteclassificationprocedure.ThispaperproposesanewformulationforcharacterizingdesignsitesinaccordancewiththeAlgerianseismicbuildingcode(RPA99/ver.2003),throughtransferfunctions,byfollowingastochasticapproachcombinedtoastatisticalstudy.Foreachsoiltype,thedeterministiccalculationoftheaveragetransferfunctionisperformedoverawidesampleof1-Dsoilprofiles,wheretheaverageshearwave(S-W)velocity,Vs,insoillayersissimulatedusingrandomfieldtheory.Averagetransferfunctionsarealsousedtocalculateaveragesitefactorsandnormalizedaccelerationresponsespectratohighlighttheamplificationpotentialofeachsitetype,sincefrequencycontentofthetransferfunctionissignificantlysimilartothatoftheH/Vamplificationcurve.ComparisonisdonewiththeRPA99/ver.2003andEurocode8(EC8)designresponsespectra,respectively.Intheabsenceofgeophysicaldata,theproposedclassificationapproachtogetherwithmicro-tremormeasurescanbeusedtowardabettersoilclassification.

简介：Siteengineeringseismicsurveyprovidesbasicdataforseismiceffectanalysis.Asanimportantparameterofsoil,shear-wavevelocityisusuallyobtainedthroughwavevelocitytestinginborehole.Inthispaper,thepassivesourcesurface-wavemethodisintroducedintothesiteengineeringseismicsurveyandpracticallyappliedinanengineeringsiteofShijingshanDistrict.Byrecordingtheubiquitousweakvibrationontheearthsurface,extractthedispersioncurvefromthesurface-wavecomponentsusingtheSPACmethodandobtaintheshear-wavevelocitystructurefrominversion.Overthedepthof42munderground,ittotallyconsistsoffivelayerswithinterfacedepthof3.31,4.50,7.23,17.41,and42.00m;andshear-wavevelocityof144.0,198.3,339.4,744.2,and903.7m/s,respectively.Theinversionresultisusedtoevaluatesiteclassification,determinethemaximumshearmodulusofsoil,providebasisforfurtherseismichazardanalysisandsiteassessmentorsitezoning,etc.Theresultshowsthatthepassivesourcesurface-wavemethodisfeasibleinthesiteengineeringseismicsurveyandcanreplaceboreholes,shortensurveyperiod,andreduceengineeringcosttosomeextent.

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