考虑风浪相关性的列车桥梁耦合振动分析

Analysis on coupled vibration of train-bridge system by considering wind and wave correlation

为研究风浪联合作用下跨海铁路桥梁列车桥梁运营的安全性和舒适性,根据实测数据,采用Copula分布模拟风速和浪高之间的相关性,得出了不同联合回归期下的风浪组合值.以某双塔斜拉桥为研究对象,计算车桥系统在风浪联合作用、仅横风作用及仅波浪作用下列车过桥时的动力响应.结果表明:桥梁和车辆的动力响应随风速和波高的增加而增大,桥梁各项指标均满足安全限值,其中横向位移变化明显,竖向位移与加速度则变化不大;当重现期为15 a时,风浪联合作用(WWVB)系统列车轮重减载率超出了安全限值;相比横风荷载,波浪荷载对车桥系统响应影响相对较小,但其对车辆横向加速度及轮重减载率的影响大于10%,因而建议考虑风浪联合作用.

To study the safety and comfort of train-bridges service on sea-crossing railway bridges under combined wind and wave action,the correlation between the wind speed and the wave height was simulated by Copula function based on the measured data,and the values of wind-wave in different joint return periods were obtained.A twin-tower cable-stayed bridge was used as a research object to study the dynamic responses of the vehicle-bridge system when the train crosses the bridge under the wind-wave action,cross-wind action only and wave action only.The results show that the dynamic response of the bridge and the vehicle increases with the increase of the wind speed and the wave height.All the indicators of the bridge meet the safety limits.The lateral displacement changes significantly,while the vertical displacement and acceleration change slightly.When the return period is 15 a,the wheel unloading rate of the wind-wave-vehicle-bridge(WWVB)system exceeds the safety limit.Compared with the cross-wind load,the wave load has less influence on the vehicle bridge system response,but it has more than 10%influence on lateral accelerate and wheel unloading rate.Therefore,it is suggested to consider the combined action of wind and wave.