简介:一台创新可变僵硬设备基于数字模拟被建议并且调查。设备,叫了一个合拢的可变僵硬弹簧(FVSS),能广泛地被使用,特别在有适应僵硬的调节集体dampers(TMD)。FVSS的一个重要特征是它的能力通过在它的支持之间的距离的一个小面值硬币改变在更低、上面的界限之间的僵硬。这个特殊特征在更短的时间间隔导致更低的时间落后错误和重新调整。设备的管理方程与类似的元素为对称的FVSS被导出并且简化。这台设备然后被用来控制single-degree-of-freedom(SDOF)象multi-degree-of-freedom(MDOF)一样的结构经由半活跃的TMD的结构。数字模拟被进行为这些结构比较几个控制案例。使它更现实主义,有它的自己的限制的一台真实直接当前的马达没有限制除了一个理想的控制案例被模仿,两个都,结果被比较。建议设备能有效地被用来压制结构的不受欢迎的颤动并且更加与一台被动设备相比改进控制器的表演,这被显示出。
简介:AnanalyticalsolutionforscatteringofplanePwavesbyasemi-cylindricalhillwasderivedbyusingthewavefunctionexpansionmethod,andconvergenceofthesolutionandaccuracyoftruncationwereverified.Theeffectofincidentfrequencyandincidentangleonthesurfacemotionofthehillwasdiscussed,anditwasshownthatahillgreatlyamplifiesincidentplanePwaves,andmaximumhorizontaldisplacementamplitudesappearmostlyattheinclinedincidenceofwaves,whicharelocatedatthehalf-space;andmaximumverticaldisplacementamplitudesemergemostlyattheverticalincidenceofwaves,whicharesituatedatthehill.
简介:Adualisolationproblemforrotatingmachinesconsistsofisolationofhousingstructuresfromthemachinevibrationsandprotectionofmachinesduringanearthquaketomaintaintheirfunctionality.Desirablecharacteristicsofmachinemountsfortheabovetwopurposescandiffersignificantlyduetodifferenceinnatureoftheexcitationandperformancecriteriainthetwosituations.Inthispaper,relevantresponsequantitiesareidentifiedthatmaybeusedtoquantifyperformanccandsimplifiedmodelsofrotatingmachinesarepresentedusingwhichtheserelevantresponsequantitiesmaybecalculated.Usingrandomvibrationapproachwithastationaryexcitation,itisshownthatsignificantimprovementinseismicperformanceisachievablebypropermountdesign.Resultsofshakingtableexperimentsperformedwitharealisticsetupusingacentrifugalpumparepresented.Itisconcludedthatasolutiontothisdualisolationproblemliesinasemi-active.mountcapableofswitchingitspropertiesfrom‘operation-optimum'to‘seismic-optimum'attheomsetofaseismicevent.
简介:Thispaperpresentsaclosed-formsolutionfordiffractionofplaneSHwavesbyasemi-circularcavityinhalf-spacebyusingwavefunctionexpansionmethod.Accuracyofthesolutionischeckedbythedisplacementresidualandstressresidualalongtheboundaries.Numericalresultsshowthattherearenotabledifferencesforresponseamplitudesbetweenasemi-circularcavityandawhole-circularcavityinahalf-space.
简介:Faultparametersareimportantinearthquakehazardanalysis.Inthispaper,theoreticalrelationshipsbetweenmomentmagnitudeandfaultparametersincludingsubsurfacerupturelength,downdiprupturewidth,rupturearea,andaverageslipoverthefaultsurfacearededucedbasedonseismologicaltheory.Thesetheoreticalrelationshipsarefurthersimplifiedbyapplyingsimilarityconditionsandanuniqueformisestablished.Then,combiningthcsimplifiedtheoreticalrelationshipsbetweenmomentmagnitudeandfaultparameterswithseismicsourcedataselectedinthisstudy,apracticalsemi-empiricalrelationshipisestablished.Theseismicsourcedataselectedisalsotousedtoderiveempiricalrelationshipsbetweenmomentmagnitudeandfaultparametersbytheordinaryleastsquareregressionmethod.Comparisonsbetweensemi-empiricalrelationshipsandempiricalrelationshipsshowthattheformerdepictdistributiontrendsofdatabetterthanthelatter.Itisalsoobservedthatdowndiprupturewidthsofstrikeslipfaultsaresaturatedwhenmomentmagnitudeismorethan7.0,butdowndiprupturewidthsofdipslipfaultsarenotsaturatedinthemomentmagnituderangesofthisstudy.
简介:与1°x的分辨率基于活跃外壳的块构造,全新统活断层和波速结构1°,为中国大陆的构造压力紧张域的一个二维的有限元素模型在纸被构造。用GPSmeasurements,然后,为模型的速度边界条件被推出中国大陆的今日的压力紧张地的年变化模式被模仿。结果证明(1)在中国大陆的最近的构造变形的一般模式被它的包围盘子的相互作用管理,哪个,印度板起一个主要作用。在中国大陆的西方有指导NNE的速度分布。最大值滑倒率出现在碰撞边界。指导北方的部件减少,当指导theeast的部件从南方逐渐地增加到北方并且从西方到东方时。在东方部分,有一个一般指导东方的运动,与在中国大陆的今日的构造应力场经历了的指导南方的部件(2)的某个数量最近的年里的改进的过程,并且这个过程介绍作为中心从Qinghai-Xizang(西藏)高原向东放射的一个一般模式。一般模式类似于周围的构造应力场,显示中国大陆上的当代的构造变形的继承。(3)最大的主要紧张介绍在东方在西方和low高的一个明显的模式。在西方的构造运动在东方是比那强壮的。Largeactive差错都位于最大的主要紧张的高值的地区。然而,紧张的大小在活跃的外壳的块的内部是更小的,它被这些差错围住。(4)四川云南区域的压力紧张地是唯一的。它不能被盘子的碰撞独自管理但是外部活跃的块的运动的联合,在下地壳或上地幔和特殊构造几何学的材料流动(例如东方喜玛拉雅的句法)也。
简介:有关与不对称的集体分发减轻prototypal框架结构的latero扭力的地震反应的滑稽得多的任务的理论、实际的问题被接近。有对interstory飘移起作用的嵌入的magnetorheologicaldampers的V形臂章背带被用来保证另外的精力驱散。采用经由反馈管理更潮湿的特征的修正的半活跃的控制策略根据一个H2/LQG标准,实际力量被片断最佳的逻辑关于调整基于最佳的力量的选择。一个动态观察员被用来通过加速传感器的非并置的放置估计状态。包括半活跃的保护系统的设计,modelization,和实现阶段在整个复杂过程要探讨的几个方面被讨论。最后,获得减轻运动的试验性的结果在一个大规模实验室原型由地面刺激导致了,模仿一座二故事的大楼的地震反应,被总结。
简介:Beam-columnorbeam-wallconnectionsareanimportantprobleminhigh-risebuildings.Inthisstudy,basedontheanalysisofanexamplestructure,ananalyticalmodelfordesignofthesemi-rigidconnectionsbetweensteelbeamsandRCwallsinhigh-risehybridbuildingsisproposed.Also,themechanicalcharacteristicsoftheseconnectionssubjectedtolowreversedcyclicloadingareinvestigatedthroughcomparisonofexperimentalresultsfromthreesemi-rigidconnectionsandtworigidconnections.Moreover,somelatentproblemsfordesignoftheseconnectionsaswellasthecorrespondingsolutionsarediscussed.Theresultsfromtheexperimentsandanalysesindicatethatsemi-rigidconnectionsexhibitsatisfactorycapacityandseismicperformance,andtheproposeddesigncanbeusedinpractice.
简介:Thisstudyinvestigatestheeffectivenessofthenon-smoothsemi-activecontrolalgorithmonsuppressingthevibrationperformanceofabuildingstructuresubjectedtoseismicwaves.AccordingtotheLyapunovstabilitytheory,ithasbeneproventhatthenon-smoothsemi-activecontrolalgorithmcanachieveafinite-timestabilityofthevibrationrelativetotheisolationlayerofabuildingstructure.Throughnumericalsimulationoftwobuildingswithdifferentparameterssubjectedtotheinputofaseismicwave,thevibrationconditionsofpassivecontrol,LQRsemi-activecontrolandnon-smoothsemiactivecontrolarecomparedandanalyzed.Thesimulationresultsshowthatthenon-smoothsemi-activecontrolalgorithmhasabetterrobustnessandeffectivenessinrestrainingtheimpactofearthquakesonthestructure.
简介:基础孤立的结构被发现了在在由于可以在近来源的地面运动存在的长时期脉搏的近差错的区域的风险。包括被动、活跃、半活跃的控制系统,各种各样的控制策略被调查了克服这个问题。这研究基于在相应于各种各样的地震危险层次的摇晃的地面的不同层次期间从一座孤立的大楼期望的几个性能层次集中于一个半活跃的控制算法的开发。建议基于表演的算法基于著名半活跃的skyhook控制算法的一个修改版本。取决于摇晃的水平的控制获得在结构上强加了的建议控制算法变化。建议控制系统用在受到七个放大地面运动记录的一座基础孤立的基准大楼上执行的一系列分析被评估了。模拟结果证明最新建议的算法在改善是有效的结构并且为选择地震的大楼的nonstructural性能。
简介:Theearth’ssurfaceirregularitiescansubstantiallyaffectseismicwavesandinduceamplificationsofgroundmotions.Thisstudyinvestigateswhetherandhowthesourcecharacteristicsaffectthesiteamplificationeffects.Ananalyticalmodelofalinesourceofcylindricalwavesimpingingonanalluvialvalleyisproposedtolinkthesourceandsite.Theanalyticalsolutiontothisproblemprovesoneaspectofthestrongeffectofsourceonsiteamplification,i.e.,thewavecurvatureeffect.Itisfoundthatthesiteamplificationdependsonthesourcelocation,especiallyunderconditionsofasmallsource-to-sitedistance.Whetherthedisplacementisamplifiedorreducedandthesizeoftheamplificationorreductionmaybedeterminedbythelocationofthesource.Itissuggestedthattraditionalstudiesofsiteresponses,whichusuallyignorethesourceeffect,shouldbefurtherimprovedbycombiningthesourcewithsiteeffects.