简介：Significantpostseismicdeformationofthe2008MW7.9WenchuanearthquakehasbeenobservedfromGPSdataofthefirst14daysaftertheearthquake.Thepossiblemechanismsfortherapidpostseismicdeformationareassumedtobeafterslipontheearthquakeruptureplaneandviscoelasticrelaxationofcoseismicllystresschangeinthelowercrustoruppermantle.WefirstlyusetheconstrainedleastsquaresmethodtofindanafterslipmodelwhichcanfittheGPSdatabest.Theafterslipmodelcanexplainnear-fielddataverywellbutshowsconsiderablediscrepanciesinfittingfar-fielddata.Toestimatetheeffectduetotheviscoelasticrelaxationinthelowercrust,wethenignorethecontributionfromtheafterslipandattempttoinverttheviscositystructurebeneaththeLongmenshanfaultwheretheWenchuanearthquakeoccurredfromthepostseismicdeformationdata.Forthispurpose,weuseaviscoelasticmodelwitha2DgeometrybasedonthegeologicalandseismologicalobservationsandthecoseismicslipdistributionderivedfromthecoseismicGPSandInSARdata.Bymeansofagridsearchwefindthattheoptimumviscosityis9×1018Pa·sforthemiddle-lowercrustintheChengduBasin,4×1017Pa·sforthemiddle-lowercrustintheChuanxiPlateauand7×1017Pa·sforthelowvelocityzoneintheChuanxiplateau.Theviscoelasticmodelexplainsthepostseismicdeformationobservedinthefar-fieldsatisfactorily,butitisconsiderablyworsethantheafterslipmodelinfittingthenear-faultdata.Itsuggeststhereforeahybridmodelincludingbothafterslipandrelaxationeffects.Sincetheviscoelasticmodelproducesmainlythefar-fieldsurfacedeformationandhasfewerdegreeoffreedoms(threeviscosityparameters)thantheafterslipmodelwithahugenumberofsourceparameters,wefixtheviscositiystructureasobtainedbeforebutredeterminetheafterslipdistributionusingtheresidualdatafromtheviscoelasticmodeling.Theredeterminedafterslipdistributionbecomesphysicallymorereas

简介：OnNovember16,2007,GeorgeC.Lee,theeditor-in-chiefofourjournal-EarthquakeEngineeringandEngineeringVibration(EEEV),wasamong11peopletoreceivea2006PresidentialAwardforExcellenceinScience,

简介：Basedontheelasticdislocationtheory,multilayeredcrustalmodel,andrupturemodelobtainedbyseismicwaveforminversion,wecalculatedthecoandpost-seismicsurfacedeformationandgravitychangescausedbytheYushuMW6.9earthquakeoccurredonApril14,2010.TheobservedGPSvelocityfieldandgravityfieldinYushuareasaredisturbedbythecoandpost-seismiceffectsinducedbyYushuearthquake,thusthetheoreticalcoandpost-seismicdeformationandgravitychangeswillprovideimportantmodificationforthebackgroundtectonicmovementofYushuandsurroundingregions.ThetimerelaxationresultsshowthattheinfluencesofYushuearthquakeonYushuandsurroundingareaswilllastaslongas30to50years.Themaximumhorizontaldisplacement,verticalupliftandsettlementareabout1.96,0.27and0.16m,respectively,themaximalpositiveandnegativevalueofgravitychangesare8.892×10-7m·s-2and-4.861×10-7m·s-2,respectively.Significantspatialvariationscanbefoundonthecoandpost-seismiceffects:Theco-seismiceffectmainlyconcentratesintheregionneartherupturefault,whileviscoelasticrelaxationmostlyactsonthefarfield.Therefore,whenusingthegeodeticdatatoresearchtectonicmotion,weshouldnotonlyconsidertheeffectofco-seismiccausedbyearthquake,butalsopayattentiontotheeffectofviscoelasticrelaxation.

简介：The2009MW7.8Fiordland(NewZealand)earthquakeisthelargesttohaveoccurredinNewZealandsincethe1931MW7.8Hawke'sBayearthquake,1000kmtothenorthwest.InthispapertwotracksofALOSPALSARinterferograms(oneascendingandonedescending)areusedtodeterminefaultgeometryandslipdistributionofthislargeearthquake.Modelingtheeventasdislocationinanelastichalf-spacesuggeststhattheearthquakeresultedfromsliponaSSW-NNEorientatedthrustfaultthatisassociatedwiththesubductionbetweenthePacificandAustralianPlates,withobliquedisplacementofupto6.3m.ThisfindingisconsistentwiththepreliminarystudiesundertakenbytheUSGSusingseismicdata.

简介：Near-fieldstronggroundmotionsareusefulforengineeringseismologystudiesandseismicdesign,butdenseobservationnetworksofdamagingearthquakesarestillrare.Inthisstudy,basedonthestrong-motiondatafromtheMw6.6Lushanearthquake,thegroundmotionparametersindifferentspatialregionsaresystematicallyanalyzed,andthecontributionsfromdifferenteffects,likethehanging-walleffect,directivityeffect,andattenuationeffectareseparatedtotheextentpossible.DifferentengineeringparametersfromtheobservedgroundmotionsarecomparedwiththelocaldesignresponsespectraandanewattenuationrelationofWesternChina.Generalresultsindicatethatthehighfrequencygroundmotion,likethepeakgroundacceleration,ontwosidesofthefaultplaneissensitivetothehanging-walleffect,whereasthelowfrequencygroundmotion,likethelongperiodspectralacceleration,intherupturepropagationdirectionisaffectedbythedirectivityeffect.Moreover,althoughtheMw6.6Lushanearthquakeisnotalargemagnitudeevent,thespatialdifferenceofgroundmotionisstillobvious;thus,forathrustfaultingearthquake,inadditiontothehangingeffect,thedirectivityeffectshouldalsobeconsidered.

简介：

简介：TemporalchangesinsiteeffectsareobtainedusingtheHVSR(horizontal-to-verticalspectralratio)methodandstrongmotionrecordsaftertheMw7.6Chi-Chiearthquake,Taiwan.Seismicdatarecordedbetween1995and2010areused,comprising3,708datafrom15stationsadjacenttotheChelungpufault.Temporalfluctuationsaredeterminedbyanalyzingthesiteeffectvariationusingatime–frequencyvariation(TFV)diagrambasedontheseseismicdata.Stationsadjacenttothefaultshowsignificantdisturbancesintheresonancefrequencyat16–26Hz.StationTCU129showsa40%dropinfundamentalfrequencyafterthemainshock,andagradualreturntotheoriginalstateovernineyears.Forstationslocatedfartherfromthefaultzone,suddenchangesintectonicstressplayadominantroleintemporalchangestotheHVSR.Animpactanalysisofthedirectionalfactorconfirmsourfindingthattheproximityofthefaulttoseismicstationshasthemostinfluenceondata.

简介：过去常在在当前的地震代码采用的基于力量的设计过程决定力量减小因素的最重要的参数是结构的韧性。为在一个灵活基础上支持的结构，韧性因素能被基础依从影响。在当前的代码给的韧性因素主要被分配忽略这研究的目的是在像栈的结构的韧性因素上估计SSI现象的意义的SSI并且因此的效果。像栈的结构的使变形的配置就非线性的时刻弯曲关系而言作为横梁元素的一个集合被理想化，当一个线性摇摇摆的模型被实现为支持的土壤建模时。用一套人工的记录，重复了线性、非线性的分析被逐渐地在非线性的分析增加加速的紧张到首先在线性、非线性的分析钢让步被观察的水平和相应于栈倒塌的水平执行。无弹性、有弹性的电阻之间的差别以排水量韧性因素被确定了。结果显示基础灵活性能减少系统的韧性并且忽视这现象可以在灵活地支持的R/C像栈的结构的地震表演的预言导致错误的结论。

简介：DearContributors,ReadersandFriends:2011milestonesthetenthanniversaryoftheJournalofEarthquakeEngineeringandEngineeringVibration.wefirstwanttotakethisopportunitytoexpressourgratitudetothoseretiringmembersoftheEditorialBoardfortheirvaluablecontributionsinthepast,andtowelcomethosewhojoinedtheEditorialBoardthisyear.AswementionedinourmessagetoyouinDecember2010,effective20ll,thejournalisofficiallyco-sponsoredbytheHuixianEarthquake

简介：为了提高卫星云图在天气预报中应用的及时有效性,经常需要尽快显示实时接收的卫星数据云图.各省气象台中规模利用站接收的FY2C卫星云图的实时数据,格式为gpf,需要先进行通道分离后才能显示图像,本文主要介绍各种投影类型的gpf数据经通道分离后,对其单通道云图进行小波分析,以便简单直观地分析云图的特征、提高云图的传输效率.

简介：本文基于可信概率水准的破坏性强震作用，针对小湾高拱坝进行了考虑坝体材料非线性的拱坝地震反应分析。在分析模型中，同时考虑了无约束域地震能量辐射效应和近域地基材料非均匀性的影响。为了实现非线性条件下的静、动力组合分析，利用显式有限元结合修正的黏弹性人工边界的开放系统时域静、动力统一分析方法进行了求解，对在自重作用下的初始静力解计算采用了动力松弛技术。

简介：本文尝试使用了一种图形编程语言进行数据解码和仿真研究,阐述了用该语言实现EDAS-C24型数字测震仪实时数据流的解码过程,提出了在G语言下利用数字滤波器逼近模拟积分器及模拟微分器响应实现对解码数据实时仿真的方法,并通过设定频带宽度,比较了设计的补偿滤波响应和实际的幅频响应的一致性.结果表明,在设定的频带内,补偿滤波响应和实际的幅频响应是一致的,仿真的精度是理想的,成果已经在广东省地震科普馆的地震互动区部署运行,取得了一定的实效.