轨道不平顺随机性对高速铁路桥梁动力响应的影响  

Effect of Stochastic Track Irregularity on Dynamic Response of High-speed Railway Bridges

作　　者：辛莉峰 李小珍[1] 肖林[1] 王铭[1] XIN Lifeng;LI Xiaozhen;XIAO Lin;WANG Ming(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031

出　　处：《铁道学报》2021年第4期150-157,共8页Journal of the China Railway Society

基　　金：四川省科技厅项目(2015HH0058)。

摘　　要：轨道不平顺是车桥耦合系统中最主要的激励源。既有车桥耦合振动研究通常采用时频转换法将规范轨道谱变换为空间随机序列,以此体现轨道不平顺的随机特征。然而,实际线路中的轨道谱具有显著的随机性,亟待开展考虑轨道不平顺全概率特性的车桥耦合系统随机振动研究。依据车辆、结构动力学理论,在合理构造车辆、有砟轨道、桥梁子系统模型及表达其相互作用原理的基础上,建立三维车-轨-桥耦合计算模型,通过与现场实测数据进行对比,证明了模型的可靠性。在此基础上,引入概率密度演化及极值分析方法,结合新提出的轨道不平顺概率模型,探究了轨道随机不平顺对桥梁动力响应的影响。计算结果表明,轨道不平顺的随机性对桥梁加速度响应有较大的影响,但在当前的轨道不平顺激扰下,系统响应并未超过规范限值。Track irregularities may be the most important source of excitation in the train-bridge coupling system.In order to reflect the random characteristics of track irregularities,current studies on train-bridge interactions usually take the time-frequency transformation method to generate the spatial track irregularity sets from the standard track spectrum.Given the significant randomness of the track spectra in the real word,further stochastic vibration analysis is required on train-bridge system under track irregularities with full probability.Based on the dynamic theories for vehicle and structure,this paper presented a three-dimensional train-rail-bridge coupling calculation model,where the train,ballasted track,bridge and the interactions among them were meticulously established.The reliability for the associated computer program was verified through a comparison with the field measured data.Furthermore,with combination of probability density evolution method and extreme value analysis,the effects of random track irregularities on the dynamic responses of bridge were clarified by a numerical analysis with a new track irregularity probabilistic model.The results indicate that the variability of track irregularities exerts a profound influence on the bridge acceleration response.However,the dynamic responses are within the limit specified by the code subjected to the track irregularity excitations in the case.

关 键 词：车辆-桥梁耦合动力学 随机振动 轨道不平顺概率模型 动力可靠度 

分 类 号：U24[交通运输工程—道路与铁道工程] TB123[理学—工程力学]