考虑突发断索事故的车桥系统动力行为分析方法  

Dynamic behavior analysis method for vehicle-bridge system considering abrupt cable-breakage events

作　　者：李岩[1] 杨孝鹏 陈逸民 Li Yan;Yang Xiaopeng;Chen Yimin(School of Transportation Science and Engineering,Harbin Institute of Technology,Harbin 150090,China;College of Civil Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]哈尔滨工业大学交通科学与工程学院,哈尔滨150090 [2]湖南大学土木工程学院,长沙410082

出　　处：《东南大学学报（自然科学版）》2023年第6期1156-1164,共9页Journal of Southeast University：Natural Science Edition

基　　金：国家重点研发计划资助项目(2021YFB2600500);国家自然科学基金资助项目(52078164),。

摘　　要：为实现缆索体系桥梁在突发断索事故中的运营安全分析,考虑桥梁拉索突发破断事故全过程特征,提出一种考虑模态信息更新和时变步长的车桥耦合系统动力行为分析方法.通过细化断索过程的计算步长,考虑断索前后桥梁模态信息的时变特征,实现断索事件下车桥系统动力响应的精细化分析.基于所提出方法,依托斜拉桥算例并采用数值模拟分析了断索作用对车桥系统动力行为的影响.结果表明:单根拉索断裂可引起桥梁频率变化2.56%;单根拉索断裂引起的主梁断面动力响应增幅最高可达80%~140%;与断裂拉索横向对称位置拉索的索力动力放大效应最为显著,达到2.16;过桥车辆的车体竖向加速度幅值约为无断索时的10倍,是威胁过桥交通安全的主要因素.To achieve operational safety analysis of cable system bridges in the abrupt cable-breakage events,a dynamic behavior analysis method for vehicle-bridge system considering the updating of modal information and time-varying step size was proposed,considering the entire process characteristics of the abrupt cable-breakage events.By refining the calculation step and considering the change of bridge modal information in the process of cable breaking,the refined calculation of dynamic response of vehicle-bridge system under cable-breaking event was realized.Based on the proposed method,numerical simulations were conducted to analyze the impact of cable breakage on the dynamic behavior of the vehicle-bridge system using a cable-stayed bridge example.The results show that single cable breakage can cause a 2.56%frequency change of the bridge,and the dynamic response of the girder section caused by the single cable breakage can increase up to 80%-140%.The dynamic amplification effect of the cable force at the transverse symmetric position of the broken cable is the most significant,reaching 2.16.The vertical acceleration amplitude of vehicle body is about 10 times of that without broken cable,which is the main factor threatening driving safety.

关 键 词：索体系桥梁 斜拉索 断索作用 车桥耦合 模态更新 

分 类 号：U447[建筑科学—桥梁与隧道工程] U441.3[交通运输工程—道路与铁道工程]