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99 个结果
  • 简介:Thispaperpresents2.5DscatteringofincidentplaneSHwavesbyacanyoninlayeredhalf-spacebytheindirectboundaryelementmethod(IBEM).Thefreefieldresponseiscarriedouttogivethedisplacementsandstressesonthelinewhichformsboundaryofthecanyon.ThefictitiousuniformmovingloadsareappliedtothesamelinetocalculatetheGreen'sfunctionsforthedisplacementsandstresses.Theamplitudesoftheloadsaredeterminedbytheboundaryconditions.Thedisplacementsduetothefreefieldandfromthefictitiousuniformmovingloadshavetobeaddedtoobtainthewholemotion.Thenumericalresultsarecarriedoutforthecasesofacanyoninhomogenousandinonelayeroverbedrock.Theresultsshowthatthe2.5Dwavescatteringproblemisessentiallydifferentfromthe2Dcase,andthereexistdistinctdifferencesbetweenthewaveamplificationbyacanyoninlayeredhalf-spaceandthatinhomogeneoushalf-space.Thereasonsforthedistinctdifferenceareexplored,andtheeffectsofthethicknessandstiffnessofthelayerontheamplificationarediscussed.

  • 标签: 层状半空间 平面SH波 散射问题 峡谷 入射 间接边界元法
  • 简介:2.5D有限/无限的元素途径被采用学习秘密地移动火车引起的波浪繁殖问题。包括隧道结构和土壤的部分,近的地的不规则被有限元素,和延长到无穷的远地的波浪繁殖性质建模被无限的元素建模。2.5D途径的一个特别特征是它启用一半空间的三维的反应的计算,考虑负担动人效果,用仅仅二维的侧面。尽管有限/无限的元素途径给在学习波浪繁殖的优点由移动引起了的一个伟人看的2.5D训练,注意应该被给计算方面,例如网孔建立的规则,以便避免生产不精密或错误的结果。在这份报纸,某必需品指因为在分析的考虑被加亮,与提高计算的速度的技术一起。这些观察应该在使2.5D成为有限/无限的元素证明有用的所有接近有效的。关键词扎根了颤动-2.5D有限/无限的元素-地下的火车-波浪数字-旁边支持的波浪繁殖:科学委员会在下面资助没有。NSC89-2211-E-002-020

  • 标签: 无限元法 地铁列车 地表震动 计算速度 有限元素 无限元方法
  • 简介:一个方法被建议在设计实践为使用估计地震soil-structure-interaction(SSI)效果。它对受到的2D结构适用垂直地事件砍波浪由同质的一半空间支持了。自从它保留简洁,方法是吸引人的光谱途径,克服一些困难和存在古典技术的不确,然而,它考虑身体上一致的刺激。简洁的这水平通过回答被完成能被用于免费地的5%阻尼反应系列产出设计的系列修正因素光谱考虑散布运动的纵标由相互作用效果介绍了。修正因素在结构的相对排水量和免费地的运动之间的转移功能(TF)是代表性的,它以它的最大的振幅被描述并且联系了频率。由练习工程师计算修正因素的表情被建议用实际结构的576盒子代表在参量的研究之上基于。方法在跨越大量普通基本颤动时期的10种情况中被测试。

  • 标签: 土-结构相互作用 二维模型 地震 程序 修正系数 工程实践
  • 简介:Inthispaper,weproposeanearlyanalyticexponentialtimedifference(NETD)methodforsolvingthe2Dacousticandelasticwaveequations.Inthismethod,weusethenearlyanalyticdiscreteoperatortoapproximatethehigh-orderspatialdifferentialoperatorsandtransformtheseismicwaveequationsintosemi-discreteordinarydifferentialequations(ODEs).Then,theconvertedODEsystemissolvedbytheexponentialtimedifference(ETD)method.WeinvestigatethepropertiesofNETDindetail,includingthestabilityconditionfor1-Dand2-Dcases,thetheoreticalandrelativeerrors,thenumericaldispersionrelationforthe2-Dacousticcase,andthecomputationalefficiency.Inordertofurthervalidatethemethod,weapplyittosimulatingacoustic/elasticwavepropagationinmultilayermodelswhichhavestrongcontrastsandcomplexheterogeneousmedia,e.g.,theSEGmodelandtheMarmousimodel.Fromourtheoreticalanalysesandnumericalresults,theNETDcansuppressnumericaldispersioneffectivelybyusingthedisplacementandgradienttoapproximatethehigh-orderspatialderivatives.Inaddition,becauseNETDisbasedonthestructureoftheLiegroupmethodwhichpreservesthequantitativepropertiesofdifferentialequations,itcanachievemoreaccurateresultsthantheclassicalmethods.

  • 标签: 地震波方程 时间 二维 求解 差分法 常微分方程
  • 简介:TheseismicwaveformoftheYutianMS7.3earthquake,XinjiangonFebruary12,2014wasrecordedclearlyandcompletelybytheDigitalSeismicNetworksofXinjiang,Qinghai,Tibet,andXinjiangHotanarray,sothemethodofjointlocationbyregionalseismicnetworkandseismicarraycanbeusedtoaccuratelydeterminetheearthquakesourcelocation.Thefollowingtechnologieswereusedintheprocessoflocation:(1)WeselectedseismicstationsequallylocatedaroundtheepicenteroftheMS7.3earthquakewithanaverageintervalofabout15degreesintheinitiallocation.(2)TherecordingwaveformsofYutianseismicstationwererotatedtotheradialandtangentialdirectionstopreciselyobtainthearrivaltimeofS-wavestodeterminetheepicentraldistance.(3)Thevelocitymodelwasusedinthedeterminationoflocationoftheepicenter,basedonthehistoricalrecordsofearthquakesintheareawithinaradiusof1.0°fromthesourceasthecenter,andthevelocitymodelisobtainedafterre-fittingandcalibration.(4)BasedonthewaveformrecordsoftheHotanseismicarray,themethodofwaveformbeamingwasusedtodeterminetheazimuthsandperformthecorrectionoftheepicenterlocationwiththeseazimuths.(5)Thedeterministicmethodwasusedtomeasurethesourcedepth.Finally,itisconcludedthattheYutianMS7.3mainshockhypocenterlocationis36.197°N,82.467°E,focaldepth12kmandoriginaltime17:19:48.2p.m.February12,2014.

  • 标签: 地震波形 新疆和田 精确位置 数字地震台网 区域地震台网 震源位置
  • 简介:ThispapercalculatesthestaticCoulombstresschangesgeneratedbyfourearthquakesintheYutianareaduring2008~2014separately,thendiscussesthetriggeringinfluence,theiraccumulatedCoulombstresschangesandtheirinfluenceonnearbyfaults.TheresultsindicatethattheMS5.5earthquakein2011andtheM_S7.3earthquakein2014arebothintheregionswheretheCoulombstresschangeispositive,thestresschangesare0.004MPaand0.021MPa,respectively,meaningtheyaretriggeredbypriorearthquakes.TheMS6.2earthquakein2012occurredintheplacewhereCoulombstresschangewasnegative,soitispostponedbythepriorearthquakes.TheimageofCoulombstresschangesoftheMS7.3earthquakein2014isinaccordwithaftershocks(ML≥3.0)distribution,butsomeregionsonthefaultwheretheCoulombstresschangeispositivehavefewaftershocks,andstrongaftershocksmayoccuratthesedistrictsinfuture.Inaddition,thispapercalculatestheCoulombstresschangeonnearbyfaults,andfindsthattheCoulombstresschangesofdifferentelementsintheGGCfaultareverydifferent,andmustreceivestrongtriggered-influence,thoughtheresultmaybeinfluencedbytheinputfinitefaultmodel,sothereisstillalargeearthquake-risk.TheGGN,PLC,PLWandLBWfaultswerealsotriggeredbythefourearthquakesoccurringbetween2008~2014.TheirmaximumCoulombstresschangesallexceed0.002MPa,sotheyalsohaveastrongearthquakehazard.

  • 标签: 地震触发 触发效应 静态应力 应力变化 故障模型 强余震
  • 简介:TheJuly3,2015PishanM_S6.5earthquakeoccurredintheintersectionareaoftheTarimblockandWestKunlunblockwherethemoderate-strongearthquakeshavebecomeactiveinrecentyears.Thispaperhasstudiedtheseismicityparametersoftheearthquakesequencessuchastheb-valueinthePishanregionanditsvicinity.Inaddition,wealsorelocatedtheaftershocksofthePishanM_S6.5earthquakeusingtheseismicphasereportbythedouble-differencemethod.ThetemporalandspatialvariationcharacteristicsofthePishanearthquakesequenceintherupturezoneareanalyzed.Thestudyisofgreatsignificanceintheseismichazardassessmentinthisregion.

  • 标签: 地震活动性 地震危险性评价 迁移 地震序列 中强地震 地震发生
  • 简介:BodywaveforminversionforthesourceprocesoftheFebruary3,1996Lijiang,YunnanearthquakeYANGXU1)(徐扬)MASAYUKIKIKUCHI2)(菊地正幸)YOU-JIN...

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  • 简介:TheYutianearthquakewithM_S7.3happenedonFebruary12,2014.Theprecursormonitoringabilityisweakinthatarea.Wefoundtendencyanomaliesandmiddle-andshort-termanomaliesfrommetalpendulumtiltmeasurementsinHotanseismicstationbeforetheearthquake.AndwealsocomparedtheanomalieswiththatoftheM_S7.3YutianearthquakeonMarch21,2008.Thetendencyanomaliesmeasuredbythemetalpendulumtiltmeterappearedsince2012astiltingeastward.Whilethemiddle-andshort-termanomalieswerecharacterizedbyacceleration,pauseandrapidchangeoftiltrateintwodirections.Thetendencyanomaliesofmetalpendulumtiltrecordsarethesamebeforethetwoearthquakes.Theybothhappenedintheeastdirection.However,therearedifferencesinduration,characteristicandearthquakeintervalsforthemiddle-andshort-termanomalies.

  • 标签: 中短期异常 地震台 变形 趋势异常 异常持续时间 地震间隔时间
  • 简介:Wesuccessfullyemployanautomaticcentroidmomenttensor(CMT)inversionsystemtoinfertheCMTsolutionsoftheFebruary12,2014MS7.3Yutian,Xinjiangearthquakeusingnear-fieldseismicwaveforms(4°<△<12°)observedbythevirtualChinaseismicnetworks,whichhavebeenrecentlysetup.Theresultsindicatethatthiseventoccurredonaruptureplane(strike243°,dip70°,andrake-18°),showingleft-lateralstrike-slipfaultingwithaminornormal-faultingcomponent.Thecentroidinthehorizontaldirectionislocatednearly13kmeastoftheepicenter(36.123°N,82.499°E),andthebest-fittingcentroiddepthisaround10km.Thetotalscalarmoment,M0,isretrievedwithanaveragevalueof3.05×1019N·m,correspondingtomomentmagnitudeMW6.92.Mostoftheenergyisreleasedwithinabout14s.Moreover,wediscussaboutthepotentialapplicationofthissysteminearthquakedisasterdecision.

  • 标签: 地震波形 矩张量 快速测定 质心 新疆 反演系统
  • 简介:本文将数字台网建立以来在使用数字地震记录仪中遇到的仪器设备故障及环境对仪器设备的影响加以总结。

  • 标签: 数字地震记录仪 设备故障
  • 简介:当时,本地联合不稳定性将发生吸收边界状况和地波浪方程的数字计划允许精力自发地进入计算领域。也就是说,二个计划支持普通波浪解决方案,组速度指了进计算域。消除联合不稳定性的本地人的钥匙是避免如此的波浪答案。为块团在2D波导的P-SV波浪运动的有限元素模拟,为高顺序的稳定的实现的一条途径多播送的公式被提供。与一个一致矩形的网孔,它被证明并且验证那高周波的本地联合不稳定性能被设置等于或比\大的元素尺寸的比率消除(\sqrt2\)乘到S波浪速度的P波浪速度的比率。这些结果能为发另外的吸收边界条件导致的不稳定性问题是珍贵的。

  • 标签: 多次透射公式 P-SV波 有限元模拟 耦合失稳 波导 二维
  • 简介:以2013年福建省陆海联测炸测实验工作为例,阐述了在野外流动地震监测中,利用当今最为流行的3G无线网络架构与IPSecVPN技术,应用其保密性高、应用灵活、价格低廉的优点,结合福建省地震局在地震行业网网络建设的实际情况,快速架构与地震行业网的数据通讯模式,使得野外采集数据能够迅速的传到总部指挥中心,有效的解决了野外流动地震监测中数据实时传输的问题,保障了指挥中心的快速响应与决策作用.

  • 标签: 3G无线 IPSEC VPN 野外流动地震监测 数据通讯
  • 简介:Inthispaper,accordingtotheresultsofthesatelliteimageryinterpretationandfieldinvestigation,westudytheactivefeaturesandthelatestactivetimesoftheChuxiong-Nanhuafault,theQuaternarybasinsformationmechanism,andtherelationshipbetweenthefaultandthe1680ChuxiongMs6%earthquake.SeveralQuaternaryprofilesatLvhe,NanhuarevealthatthefaulthasoffsetthelatePleistocenedepositsoftheT2andT3terracesofLongchuanriver,indicatingthatthefaultwasobviouslyactiveinlateQuaternary,TheChuxiong-NanhuafaulthasbeendominatedbydextralstrikeslipmotioninthelateQuaternary,withanaveragerateof1.6-2.Omm/a.SeveralpullapartQuaternarybasinsofChuxiong,Nanhua,andZiwuetc.havedevelopedalongthefault.The1680ChuxiongMs6%earthquakeandseveralmoderateearthquakeshaveoccurrednearthefault.TheChuxiong-Nanhuafaultaretheseismogenicstructureofthoseearthquakes,thelatestfaultmovementwasinthelate-Pleistocene,andeventheHolocene.Inlargearea,theChuxiong-NanhuafaultandtheeasternQujiangfaultandtheShipingfaultcomposedasetofNW-trendingobliqueorientationactivefaults,andthemotioncharacteristicsareallmainlydextralstrikeslip.Themotioncharacteristics,liketheredriverfaultoftheSichuan-YunnanRhombicBlocksouthwesternboundary,areconcernedwiththeescapingmovementoftheSichuan-YunnanRhombicBlock.

  • 标签: The Chuxiong-Nanhua FAULT LATE-QUATERNARY Dextral STRIKE
  • 简介:通过对发生于1999~2000年间库玛中东段地区3次5级以上地震前地下流体短临异常的分析对比,得出了该地区地下流体短临异常的时空强演化特征。

  • 标签: 地下流体 短临异常 时空强演化
  • 简介:2015年7月3日新疆皮山Ms6.5级地震灾区地处塔里木盆地南缘,该地自然条件恶劣,经济极为落后,灾区农村的民房除了抗震安居工程建设的房屋外,还有大量抗震性能较差的民居,在地震中受损严重,经济损失较大。灾区大部分位于山前溢出带,地下水位浅、地基土层软弱等场地条件对地震动有放大作用,震害影响范围较大。灾后重建中应继续加大安居富民工程的经费投入力度。灾区北部人口密集,地基土层软弱,工程地质条件差,建议在今后的安居富民建设中加强地基处理。

  • 标签: 皮山Ms6.5级地震 震害 应急科考 安居富民工程
  • 简介:对2005年3月6日台湾宜兰海域6.1级有感地震的速报情况进行总结,并对其地震特征进行了初步分析。

  • 标签: 速报分析 震相特征 震源机制
  • 简介:Anew3Dvelocitymodelofthecrustanduppermantleinthesoutheastern(SE)marginoftheTibetanplateauwasobtainedbyjointinversionofbody-andsurface-wavedata.Forthebody-wavedata,weused7190eventsrecordedby102stationsintheSEmarginoftheTibetanplateau.Thesurface-wavedataconsistofRayleighwavephasevelocitydispersioncurvesobtainedfromambientnoisecross-correlationanalysisrecordedbyadensearrayintheSEmarginoftheTibetanplateau.ThejointinversionclearlyimprovesthevSmodelbecauseitisconstrainedbybothdatatypes.Theresultsshowthatataround10kmdepththerearetwolow-velocityanomaliesembeddedwithinthreehigh-velocitybodiesalongtheLongmenshanfaultsystem.Thesehigh-velocitybodiescorrespondwellwiththePrecambrianmassifs,andthetwolocatedtothenortheastof2013MS7.0Lushanearthquakeareassociatedwithhighfaultslipareasduringthe2008Wenchuanearthquake.Theaftershockgapbetween2013Lushanearthquakeand2008Wenchuanearthquakeisassociatedwithlow-velocityanomalies,whichalsoactsasabarrierzoneforrupturesoftwoearthquakes.Generallylargeearthquakes(M≥5)intheregionoccurringfrom2008to2015arelocatedaroundthehigh-velocityzones,indicatingthattheymayactasasperitiesfortheselargeearthquakes.Jointinversionresultsalsoclearlyshowthatthereexistlow-velocityorweakzonesinthemid-lowercrust,whicharenotevenlydistributedbeneaththeSEmarginofTibetanplateau.

  • 标签: 面波频散 青藏高原 联合反演 S模型 南缘 体波
  • 简介:从中国大陆动力学环境分析入手,分析了全球强震活动对中国大陆地震活动的影响、中国大陆强震活动特征,特别是对1900年以来中国大陆8级强震后第一、第二、第三年内大陆地区6级以上地震的频次和发震地点进行了统计分析后,对我国未来3年的地震形势作出了判定。

  • 标签: 昆仑山 中国大陆 地震趋势 强震活动 大陆动力学 频次