考虑行波效应的车桥系统地震响应分析  

Random seismic response analysis of train-bridge systems considering wave travelling effect

作　　者：张志超[1] 张亚辉[1] 林家浩[1] 

机构地区：[1]大连理工大学运载工程与力学学部,工业装备结构分析国家重点实验室,辽宁大连116024

出　　处：《地震工程与工程振动》2010年第4期8-16,共9页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(10972048;90815023)

摘　　要：借助虚拟激励法,本文研究了非一致水平地震作用下三维车桥耦合时变系统的非平稳随机振动问题。通过轮轨间位移协调关系将列车和桥梁运动方程进行耦合,建立了考虑行波效应的多点地震激励下列车-桥梁时变系统运动方程。水平地震激励假设为均匀调制多点异相位完全相干随机激励;轨道不平顺激励假设为多点异相位完全相干平稳随机激励。采用时变系统的虚拟激励法将这些随机激励分别转化为一系列虚拟的确定性激励,然后通过数值积分求解相应的虚拟响应,进而方便地得到系统随机响应的时变功率谱密度函数和标准差等。数值算例中,通过Monte Carlo法验证了本文随机振动分析方法的正确性和有效性,并讨论了地震波视波速、场地土条件等对系统随机响应的影响。Non-stationary random vibration of 3-D train-bridge time-dependent systems subjected to the action of non-uniform lateral horizontal earthquake is investigated on the basis of the pseudo-excitation method（PEM）.The motion equation of train-bridge time-dependent systems due to multi-point earthquake excitations with the consideration of wave travelling effect is established by connecting the motion equations of the train and bridge through wheel-rail contact relations.The excitation of lateral horizontal earthquake is assumed to be a uniformly modulated multi-point different-phase completely coherent random excitation,while the excitations of track irregularity are assumed to be multi-phase different-phase completely coherent random excitations.The pseudo-excitation method（PEM） is extended to such time-dependent systems and is applied to transform the above random excitations into a series of deterministic pseudo excitations.After solving the correspondent pseudo responses by using the Newmark method,various non-stationary random responses including the time-dependent PSD and RMS of interested quantities can be obtained easily.Numerical examples show the effectiveness and accuracy of the presented method by comparison with Monte Carlo simulation.Additionally,the influences of seismic apparent wave velocity and site type on system random responses are discussed.

关 键 词：车桥系统 水平地震 虚拟激励法 行波效应 非平稳随机振动 

分 类 号：TU352.11[建筑科学—结构工程] U44[建筑科学—桥梁与隧道工程]