基于列车走行性的斜拉桥竖弯涡振振幅限值研究  

Amplitude limit of cable-stayed bridge vertical bending vortex vibration based on train running performance

作　　者：郭向荣[1] 岳道阔 GUO Xiangrong;YUE Daokuo(School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075

出　　处：《铁道科学与工程学报》2023年第11期4233-4242,共10页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(U1934207)。

摘　　要：为合理确定基于列车运行安全性与乘坐舒适性的斜拉桥竖弯涡激振动幅值限值,以渝黔高铁某主跨为300 m的双塔斜拉桥为工程背景,通过刚性悬挂节段模型测力试验获取其主梁与列车气动三分力系数,采用弹性悬挂节段模型测振试验测试成桥状态下主梁的涡振性能,获取桥梁的竖向涡振起振风速。将桥梁与列车视为一个整体系统,以风荷载为外部激励,以轨道不平顺为自激力,其中桥梁的涡振响应以动态轨道不平顺的形式加入,依据弹性系统动力学总势能不变值原理以及形成矩阵的“对号入座”法则建立风-车-桥耦合系统振动方程,研究桥梁发生不同振幅及初始相位竖向涡振情况下,列车以不同行车速度通过桥梁时的桥梁动力响应指标和列车脱轨系数、轮重减载率、车体振动加速度、Sperling舒适性指标等,确定在考虑列车运行安全性和乘坐舒适性情况下的斜拉桥竖弯涡振振幅限值。研究结果表明:列车运行速度分别为250,275,300,325和350 km/h时,该斜拉桥竖弯涡振振幅限值分别为3.5,3.0,2.5,2.3和1.8 cm。基于列车走行性计算确定的桥梁竖弯涡振振幅限值较《公路桥梁抗风设计规范》中对桥梁竖弯涡振振幅限值的规定更具参考价值,较基于车体加速度峰值及其变化率确定的桥梁竖弯涡振振幅限值更加合理。In order to determine the amplitude thresholds of cable-stayed bridge vertical vortex-induced vibration(VVIV)based on train operation safety and riding comfort,taking a twin tower cable-stayed bridge with 300 m main span in Chongqing-Guizhou high-speed railway as the engineering background,the three component coefficients of the main beam and the train were obtained by the force measurement test of the rigid suspension segment model.The vortex vibration performance of the main beam under the bridge completion state was tested by the vibration measurement tests of the elastic suspension segment model to obtain the starting wind speed of VVIV.The bridge and train were regarded as a whole system,with wind load as external excitation and track irregularity as self-excited force.The VIV response of the bridge was added in the form of dynamic track irregularity.The vibration equation of wind-vehicle-bridge coupling system was formulated by means of the principle of total potential energy with a stationary value in elastic system dynamics and the“set-in-right-position”rule.The dynamic response index of the bridge,train derailment coefficient,wheel unloading rate,vehicle vibration acceleration and Sperling comfort index were calculated and analyzed when the train passes through the bridge at different speeds under different amplitudes and initial phases of VVIV.The amplitude thresholds of VVIV considering train operation safety and riding comfort was finally determined.The results show that when the train speeds are 250,275,300,325 and 350 km/h,the vortex vibration amplitude limits of the vertical bending of the bridge are 3.5,3.0,2.5,2.3 and 1.8 cm.The amplitude thresholds of cable-stayed bridge VVIV determined based on the calculation of train running performance is more valuable than it in the Code for Design of Highway Bridge Wind Resistance,and is more reasonable than it determined based on the train peak acceleration and its time-varying rate.

关 键 词：桥梁工程 斜拉桥 涡振振幅限值 风-车-桥耦合振动 风洞试验 列车走行性 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]