三维随机激励作用下斜拉索参数振动的有限元分析  

Finite Element Analysis of Parametric Vibration of Stayed Cable Under Three-Dimensional Random Excitation

作　　者：李永乐[1] 孙超[1,2] 向活跃[1] 王磊[1] 

机构地区：[1]西南交通大学桥梁工程系,四川成都610031 [2]沈阳铁路局,辽宁沈阳110001

出　　处：《桥梁建设》2017年第2期19-24,共6页Bridge Construction

基　　金：国家科技支撑计划课题(2012BAG05B02);交通运输部建设科技计划项目(2014318800240)~~

摘　　要：为了解风荷载和车辆荷载作用下斜拉索的位移响应,以某双塔斜拉桥为例,建立斜拉索的有限元模型,采用时域抖振分析和车-桥耦合振动分析方法,得到风荷载和车辆荷载作用下斜拉索的索端位移激励,对斜拉索参数振动进行分析,分别讨论了不同方向索端位移激励下斜拉索的位移响应,并分析了风速及车速的影响。结果表明:风荷载引起的随机位移激励作用下,斜拉索的位移响应随风速的增加逐渐增大,但较正弦激励作用下的响应小;车辆荷载引起的随机位移激励对斜拉索中点的位移响应影响很小;顺桥向的随机位移激励对斜拉索的垂向位移响应影响较大,横桥向的随机位移激励对其影响较小。To have an understanding of the displacement responses of the stayed cable under the wind and vehicle loads, a double-pylon cable-stayed bridge was taken as an example, the finite element model for the cable was established and by the analysis methods of the time-domain buffeting and the vehicle and bridge coupling vibration, the cable end displacement excitation under the wind and vehicle loads was acquired. The parametric vibration of the cable was analyzed, the displacement responses of the cable under the cable end displacement excitation of different directions were respectively discussed and the influences of the wind and vehicle speeds were analyzed as well. The results show that under the random displacement excitation induced by the wind load, the displacement responses of the cable gradually increase with the increase of the wind speeds, but the responses are less than those under the sinusoidal excitation. The influences of the random displacement excitation induced by the vehicle load on the displacement responses at the midpoint of the cable are very little. The influences of the displacement excitation along the bridge on the vertical displacement responses of the cable are great, but the influences of the displacement excitation in the transverse direction of the bridge on the displacement responses are little. © 2017, Journal Press, China Railway Bridge Science. All right reserved.

关 键 词：斜拉桥 斜拉索 随机激励 参数振动 时域抖振 车-桥耦合 有限元法 

分 类 号：U443.38[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]