车桥系统地震响应概率统计及安全评估  

Probability statistics and safety assessment of train-bridge system under seismic response

作　　者：崔圣爱[1] 徐李麟 饶家锐 曹卓颖 崔恩旗 Cui Shengai;Xu Lilin;Rao Jiarui;Cao Zhuoying;Cui Enqi(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Heze River and Lake Basin Engineering Management Service Centre,Heze 274000,China)

机构地区：[1]西南交通大学土木工程学院,成都610031 [2]菏泽市河湖流域工程管理服务中心,菏泽274000

出　　处：《东南大学学报（自然科学版）》2023年第5期896-904,共9页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金高铁联合基金资助项目(U1834207)。

摘　　要：为研究随机地震下车桥耦合系统的动力响应特性,通过数值方法实现了车桥耦合振动的仿真计算,确定了系统响应的概率统计规律,并用于动力可靠度分析.以实际列车和典型简支梁桥建立仿真模型,合成随机地震动加速度时程样本,获取系统的动力响应,基于蒙特卡洛模拟和可靠度理论评估结构的安全特性.结果表明:随机地震下系统响应指标的变异程度不同;桥梁跨中横向位移的变异程度最高,变异系数为0.468,竖向位移的变异程度最低,变异系数为0.097;列车的轮对横向力、轮重减载率、竖向加速度以及桥梁跨中响应均符合极值Ⅰ型分布,桥梁横向响应同时符合对数正态分布;可靠度为0.99时,系统的计算响应限值最大,动车横向加速度和桥梁跨中竖向加速度限值分别超过规范限值56%和3%,桥梁功能失效和列车脱轨的风险较高.To study the dynamic response characteristics of the train-bridge coupled system under random earthquakes,the simulation calculation of a train-bridge system was carried out by numerical methods,and the probability statistical laws of the system response are determined and used for dynamic reliability analysis.A simulation model is established by an actual train and a typical simply supported girder bridge,and the dynamic response of the system is obtained by synthesizing the acceleration time samples of the random earthquakes.The safety characteristics of the structure are assessed based on Monte Carlo simulation and reliability theory.The results show that the variabilities of the system response indexes are different under random earthquakes.The bridge span mid-span transverse displacement has the highest variability,and the coefficient of variation is 0.468.While the vertical displacement has the lowest variability,and the coefficient of variation is 0.097.The wheel pair transverse force,wheel weight shedding rate,vertical acceleration and bridge mid-span response of the train all conform to the extreme typeⅠdistribution,and the bridge transverse response conforms to the lognormal distribution simultaneously.When the reliability is 0.99,the system has the maximum calculated response limits,and the limits of the transverse acceleration of the moving train and the vertical acceleration of the bridge span exceed the code limits by 56%and 3%respectively,with a high risk of bridge functional failure and train derailment.

关 键 词：地震作用 车桥耦合振动 随机振动 概率统计 可靠度 

分 类 号：U238[交通运输工程—道路与铁道工程]