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14 个结果
  • 简介:Adetailthree-dimensionalPwavevelocitystructureofBeijing,TianjinandTangshanarea(BTTarea)wasdeterminedbyinvertinglocalearthquakedata.Intotal16048Pwavefirstarrivaltimesfrom16048shallowandmid-depthcrustalearthquakes,whichoccurredinandaroundtheBTTareafrom1992to1999wereused.ThefirstarrivaltimesarerecordedbyNorthernChinaUnitedTelemetrySeismicNetworkandYanqing-HuailaiDigitalSeismicNetwork.Hypocentralparametersof1132earthquakeswithmagnitudeML=1.7~6.2andthethree-dimensionalPwavevelocitystructurewereobtainedsimultaneously.TheinversionresultrevealsthecomplicatedlateralheterogeneityofPwavevelocitystructurearoundBTTarea.Thetomographicimagesobtainedarealsofoundtoexplainotherseismologicalobservationswell.

  • 标签: 京津唐地区 地震波 P波速度结构 数字遥测地震台网 地震观测 地震活动性
  • 简介:3-DS-waveQstructureinJiashiearthquakeregionisinvertedbasedontheattenuationofseismicwavesrecordedfromearthquakesinthisregionin1998bytheResearchCenterofExplorationGeophysics(RCEG),CSB,andaroughconfigurationofdeepcrustalfaultsintheearthquakeregionispresented.First,amplitudespectraofS-wavesareextractedfrom450carefully-chosenearthquakerecords,calledobservedamplitudespectra.Then,afterinstru-mentalandsiteeffectcorrection,theoreticalamplitudespectraaremadetofitobservedamplitudespectrawithnonlineardampedleast-squaresmethodtogettheobservedtraveltimeoverQ,providedthatearthquakesourcesconformtoBrune¢sdiskdislocationmodel.Finally,by3-Draytracingmethod,theoreticaltraveltimeoverQismadetofitobservedtraveltimeoverQwithnonlineardampedleast-squaresmethod.Inthecourseoffitting,thevelocitymodel,whichisobtainedby3-Dtraveltimetomography,remainsunchanged,whileonlyQmodelismodified.Whenfittingcametothegivenaccuracy,theultimateQmodelisobtained.TheresultshowsthatanNE-trendinglowQzoneexistsatthedepthsof10~18km,andanNW-trendinglowQzoneexistsatthedepthsof12~18km.TheseroughlycoincidewiththeNE-trendingandtheNW-trendinglowvelocityzonesrevealedbyotherscientists.ThedifferenceisthatthelowQzoneshaveawiderrangethanthelowvelocityzones.

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  • 简介:Three dimensional velocity structure beneath the Kunming Telemetered Seismic Network(王椿镛)(王溪莉)(颜其中)Threedimensionalvelocityst...

  • 标签: local earthquake parameter separation METHOD APPROXIMATE
  • 简介:在这篇论文,从一座RC框架大楼的回答的时间的特征使遭到了到大余震和WenchuanMs8.0地震被介绍。从主要吃惊的扎根的运动记录从三个附近的车站被获得。加速记录以即时正切的加速被分析T,正常加速N,加速向量|a|的欧几里德几何学的标准,速度向量|ν|,排水量向量|ν|,时间的弯曲κ,κt,和时间的扭转γ和γt。在上述因素和在从广泛的分析获得的深度信息另外的一些之间的运动学的关系的结果被提供并且讨论。

  • 标签: 地面运动 时间特性 地震 汶川 三维 钢筋混凝土框架
  • 简介:IntroductionTherearemanynumericalmodelingstudiesoftopographyforMTfieldsappearedinthepastliterature,butmostoftheworksare2-Dres...

  • 标签: D FINITE DIFFERENCE METHOD 3-D topographic
  • 简介:Basedontheseismicresponsecharacteristicsofspaceframestructures,anewtypeofseismicisolationbearingdefinedasathree-dimensionalseismicisolationbearing(3DSIB)isdevelopedinthispaper.Thebearingoffersexcellentpropertiessuchasmulti-dimensionalseismicisolation,reasonablerotationcapability,goodabilitytoresistliftingload,uncoupledstiffnessinhorizontalandverticaldirections,etc.Inthe3DSIB,thehorizontaldimensionisdesignedbycombiningtheTeflonslidingdeviceandhelicalspring,whiletheverticaldimensionisdevelopedbyintroducingdiskspringsorhelicalsprings.Themathematicalmodelofthe3DSIBwasestablishedanditsperformancewiththecriticalparameterswastestedonashakingtable.Furthermore,the3DSIBwasappliedina120mspanhangarstructureandsimulatedusingSAP2000softwaretoevaluateitsperformanceinpracticalstructures.Theperformanceofthestructureswithandwithout3DSIBwascompared.Itisshownthatthehangarstructurewith3Dbearingsachievesabetterperformance.Theaxialforceandaccelerationresponseofthestructureswith3DSIBareeffectivelyreduced,whilethedisplacementresponseofthebearingiswithinthepredeterminedrange.

  • 标签: 隔震支座 三维地震 大跨度 应用 空间框架结构 SAP2000
  • 简介:Inthisstudytheseismicpoundingresponseofadjacentmulti-degree-of-freedom(MDOF)buildingswithbilinearinter-storyresistancecharacteristicsisinvestigatedthroughdimensionalanalysis.Theapplicationofdimensionalanalysisleadstoacondensedpresentationoftheresponse,andtheremarkableself-similaritypropertyforbilinearMDOFbuildingswithinelasticcollisionisuncovered.Itisshownthatwhentheresponseisexpressedintheappropriatedimensionlessform,responsespectraforanyintensityoftheexcitationcollapsetoasinglemastercurve.ThereducedΠsetexplicitlydescribestheinteractionbetweenthecollidingstructures.TheeffectofpoundingontheMDOFbuilding’sresponseisillustratedusingthreewell-dividedspectralregions(amplified,de-amplifiedandunaffectedregions).Parametricstudiesareconductedtoinvestigatetheeffectsofthestorystiffnessofstructures,thestorystiffnessratioandmassratioofadjacentbuildings,thestructuralinelasticcharacteristicsandthegapsizevalues.Resultsshowthat(i)theinfluenceofsystemstiffnessratiotothelighterandmoreflexiblebuildingismoresignificantinthefirstspectralregion,wherethemaximumresponseofthebuildingisamplifiedbecauseofpounding;and(ii)thevelocityandpoundingforceoftheheavierandstifferbuildingisunexpectedlysensitivetothemassratioofadjacentbuildings.

  • 标签: POUNDING DIMENSIONAL analysis EARTHQUAKE engineeri
  • 简介:Smoothedparticlehydrodynamics(SPH)isamesh-freeadaptiveLagrangianparticlemethodwithattractivefeaturesfordealingwiththefreesurfaceflow.ThispaperappliestheSPHmethodtosimulatethelarge-amplitudelateralsloshingbothwithandwithoutafloatingbody,andtheverticalparametrically-excitedsloshinginatwo-dimensionaltank.ThenumericalresultsshowthattheSPHapproachhasanobviousadvantageoverconventionalmesh-basedmethodsinhandlingnonlinearsloshingproblemssuchasviolentfluid-solidinteraction,andflowseparationandwave-breakingonthefreefluidsurface.TheSPHmethodprovidesanewalternativeandaneffectivewaytosolvethesespecialstrongnonlinearsloshingproblems.

  • 标签: SPH方法 大振幅 液体晃动 模拟 网格自适应 非线性晃动
  • 简介:Usingthreedimensional(3D)viscoelasticfiniteelementmethod(FEM)westudythedynamicevolutionpatternofthecoseismicchangeofCoulombfailurestressandpostseismicchange,ontimescaleofhundredsyears,ofrheologicaleffectinducedbytheMS=7.2XingtaiearthquakeonMarch22,1966.Then,wesimulatethecoseismicdisturbanceinstressfieldinNorthChinaanddynamicchangerateonone-yearscalecausedbytheXingtaiearth-quakeandTangshanearthquakeduring15yearsfrom1966to1980.Finally,wediscussthetriggeringofastrongearthquaketoanotherfuturestrongearthquake.

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  • 简介:Athree-dimensionalcrustaldensitymodelbeneathNorthChinaisdeterminedusingP-wavetraveltimesandgravitydatumbysequentialinversionmethodinthispaper.Toimprovetheuniquenessofthesolution,weusedalinearrelationshipbetweenvelocityanddensitytoachievemutualconversionsandconstraintsbetweenvelocitydifferenceanddensitydifference.Algebraicreconstructiontechnique(ART)wasusedindensityinversion,whichhighlyimprovedthecalculationspeedcomparingwithcommonleastsquaresmethod.TheinversionresultsindicatethatthecrustaldensitybeneathNorthChinaisextremelyinhomogeneouswithitsdistributioncoherentwithregionaltectonics.ThelowercrustofTaihangmountaintectoniczoneshowsanobviouslowdensitycharacteristic.Weproposedthatitmaybeanindicatorofupwellingofmantlematerialsorpartialmeltingoflowermostcrust.

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  • 简介:Wepresentaparallelhybridalgorithmbasedonpseudospectralmethod(PSM)andfinitedifferencemethod(FDM)fortwo-dimensional(2-D)globalSHwavefieldsimulation.Thewhole-EarthmodelistakenasacrosssectionofsphericalEarth,andcorrespondingwaveequationsaredefinedin2-Dcylindricalcoordinates.SpatialderivativesinthewaveequationsareapproximatedwithefficientandhighaccuracyPSMinthelateralandhigh-orderFDMintheradialdirectiononstaggeredgrids.Thisalgorithmallowsustodividethewhole-Earthintosub-domainsinradialdirectionandimplementefficientparallelcomputingonPCcluster,whileretainshighaccuracyandefficiencyofPSMinlateraldirection.Atransformationofmomenttensorbetween3-DsphericalEarthandour2-Dmodelwasproposedtogivecorrespondingmomenttensorcomponentsusedin2-Dmodeling.Comparisonofmodelingresultswiththoseobtainedbydirectsolutionmethodshowsverygoodaccuracyofouralgorithm.Wealsodemonstrateitsfeasibilitywithalateralheterogeneouswhole-Earthmodelwithlocalizedvelocityperturbation.

  • 标签: 地球模型 DM算法 PSM 混合动力 波场计算 二维
  • 简介:象lumped参数模型那样的分离模型和有限元素模型广泛地在地震的土壤扩大的解决方案被使用。然而,任何一个模型都精确地不估计土壤沉积物的自然频率,也不模仿一抑制频率独立。这研究基于模式等价方法为分层的土壤沉积物的一个维的粘弹性的反应分析开发一个新分离模型。新分离模型是一系列集中的群众,弹簧和缓冲筒与一种特殊配置描绘的一个一个维的相等的multi-degree-of-freedom(MDOF)系统。相等的MDOF系统的动态反应是导出的经分解,物理参数以形式的性质被提出。相等的MDOF系统与可得到的理论解决方案通过扩大函数的比较被验证。在相等的MDOF系统的自由(DOF)的度的适当数字被估计。有存在的相等的MDOF系统的比较研究分离模型被执行。建议相等的MDOF系统罐头确切介绍土壤存款抑制的自然频率和hysteretic并且向更精确的结果提供更少DOF,这被显示出。

  • 标签: 土壤沉积物 反应分析 粘弹性 相等 系统 MDOF