【作者】 冯星梅；

【导师】 史永吉；

【作者基本信息】 铁道部科学研究院 ， 桥梁与隧道工程， 2000， 博士

【摘要】 现代社会的进步、经济发展和人民生活水平的提高对交通运输质量（快速、安全、舒适）提出了更高的要求，为了适应这一需求，近年来我国铁路实施了分批分级的提速计划。客运由100km／h逐步提速到120、140、160、200km／h，与此相应，货运由50km／h逐步提速到60、80、100km／h。并正在实施快速和高速客运专线（200km／h－300km／h）的建设。而我国既有线上桥梁大多数为中小跨度（20－40m）简支PC T梁和钢板梁，这些过去不同时期建造的桥粱，当初设计时列车速度不高，当时的规范也未对列车通过桥梁的走行性评定作出规定。在提速中发现空载货车在以大于 60km／h速度通过中小跨度桥粱时，桥梁发生了较大的横向谐振，特别是上承式钢板梁，最大横向振幅达12mm。在客车以大于160km／h速度这些桥梁时，横向振幅也较大。因此，如何通过仿真分析再现桥梁动力响应的理论研究，如何改造既有线桥梁使之满足提速后列车走行性要求，以及研究适合快速和高速客运的桥粱结构形式，是我们今后的长期任务。 本文结合我国既有线提速和高速铁路的建设中中小跨度桥梁急需解决的问题展开了以下研究： 首先，应用大型通用结构分析程序肥C／PATRAN、MSC／NASTRAN和MSC／DYTRAN建立了列车、线路和桥梁系统的三维有限元分析较精确的模型，以车辆的速度和轨道不平顺等级作为输入条件，采用显式积分方法，在每个时间步长中依次求解整个有限元模型中各个节点的加速度、速度和位移、单元的应变率、单元应力、节点力，最终求得结构在分析时间内的加速度、位移、力等随时间变化的响应值，由轮轨接触力求得轮重减载率和脱轨系数以评定行车安全性，由车体的加速度评定运行平稳性。同时，就32米简支钢板梁桥横向振动的计算结果与实测结果进行了比较，其振幅的随机性以及强迫频率吻合较好，从而验证了本仿真分析的可信性。 此外，本文提出按余弦波周期变化的横向力作为蛇行运动的简化模型，求解了引起桥梁横向拍振的蛇行运动频率，与实测值基本接近，这对通过快速计算确定引起桥梁横向拍振的蛇行运动频率具有实用意义。 针对上承式钢板梁桥发生的横向类共振现象，基于吸能减振原理对32米上承式钢板梁桥设计了粘弹性阻尼器减振装置，并将减振装置安装于羊楼司桥上进行了实桥减振试验，取得了显著效果。 针对既有线中小跨度简支钢板梁和PCT梁在提速后山现的横向振动过大的问题，用本文建立的车线桥系统有限元模型，应用MSC／DYTRAN软件，分析了32米简支和多跨连续结合梁桥在客车以 140－300km／h速度通过时的走行性。什对我国既有线上PC T梁出现的问题，提出了加固方案并进行了走行性分析。研究结果对我国既有桥梁的改造和高速铁路桥粱建设具有重要参考价值。更多还原

【Abstract】 In modern society with the development in economy and the improvement on people’sstandard of living, the more comfortable and more efficient transportaion means is required.Furthermore, in order to increase the railway’s competitive capability to that of freeway andair transport, the train speed has been increased drastically in resent years. The speed ofpassenger trains has been increased stag by stag from less than l00 km/h to l20. l40.l60km/h or even 200km/h, and the speed of freight trains has been increased stage by stagefrom 50 km/h tO 60. 80. l00 km/h. At the same time, special railway lines for high-speedpassenger trains (200-300km/h) are being constructed. In our country bridges of existingrailway tracks are almost simple PC T-type girders and I-type steel girders of 20-40 spanlength which have been designed under the speed of l20km/h and without the considerationof running quality However, When unloaded freight trains pass through the above bridgeswith the speed higher than 60km/h, there is serious lateral resonance aroused from the bridge,especially for simple I-type Steel girder with a maximum lateral displacement of l2mm. AndWhen the passenger trains pass through the above bridges with the speed higher than l60km/h,the amplitude of the bridge’s lateral vibration also exceeds the reference value ofspecifications. So, how to simulate the dynamic response of vehicle-track -bridge system toresearch the fitfol renovation method of existing railway bridges to meet the need of therunning quality of trains by increased speed and to research the structures suitable forconstruction high speed railway are our important task.On accoullt of the urgent need of the solution of problems of existing railway bridgesand high-speed railway bridges, in this paper the following problems are researched:Firstly, the dynamic test and the numerical simulation are carried through for theYangLouSi bridge(L=32m simple I-type steel girder). The finite element method is employedin establishing the calculation model for the vehicle-track-bridge joint structure system, andMSC/DYTRAN is adopted in the calculation of contact force between wheel and rail and inanalyzing the structure system dynamic response. The speed of vehicle and the railirregularities of different grade are input. The explicit method is adopted and in every timestep the grid-point accelerations. grid-point velocities and displacements. element strainf＆tCS、CleffiCllt StfCSSCS slid CICffiCllt foFCCS t gfld polfltS sfC C8lCu18tCd．Flflslly hC ChsflgCS Ofaccele血ions、displacements and forces with time are obtained．The running safety Isevaluated by the wheel load reduction rate and derailment ratio and the riding comfort isevaluated with the咒celeMions of vehicles．Then the esults of calculatlolls e comparedwith the test values andthe randomlclty of＊thelclty lateral vibration amplitude and the forcedfrequency of＊thency two re ye0 slml你 which verify the credltablllty of＊theablllty analysis method． Moreovec the simplified analysis model ofslmulatingthe sn毗e motion as h忆raf forcechanging accoding to coslne w uue In cwle Is put fo fiNlN加．nd with this model the sn毗motlon frsrequencles that can Induce the h卜fsl esonance of the bud驴e o讪ined．Thecalculated f6sults e cons卜比＊w讪the iC砒d one，so It has p fnfntlcal meaning on quicklydetermining the sn劝“motion frequencies that can Induce the 血曰alresonance of the bridgethrough simplified analysis． To m1n河1e】atera！resonance o75e slmp！e Itwe stee！glder，6asd on enefgydlsslpatlontheom伽 vlscoelastlc damper device of32m simple N仰 st6el glder isdesigned．Then the damper device Is installed in the YangLOusi brd驴 and the duamic 5 gyetect Is conducted．yhe ie一主一一一回L大一言土d fCsultS manifest that the vlscoel一自白色一一主一一注Ic damper玉匡奎自二甲一一晖stl更多还原