强风环境下斜拉桥车桥系统动力响应分析研究

基于模态综合分析理论,在推导复杂车辆模型刚度、阻尼矩阵和建立车桥系统风荷载模型的基础上,提出一种全面考虑动力风载效应的车桥系统动力响应分析方法,结合桥例对强风环境下的斜拉桥车桥系统的动力响应进行了分析研究。结果表明:强风下桥梁竖向位移响应受风载影响显著,横向位移响应主要由风荷载控制;低风速下桥梁的振动加速度响应受风荷载影响较大;风荷载引发的桥梁振动对车辆竖向位移和加速度响应影响较大,横向响应由风载和桥梁响应控制,风载对车桥系统动力响应影响明显。所提出的方法具有较高的精度和分析效率,可为其他类型大跨桥梁的相关分析提供参考。

Dynamic Response Analysis of Vehicle-bridge System for Cable-stayed Bridge in Strong Windy Environment

A computer simulation method of solving vehicle-bridge system vibration response considering wind load was presented based on mode integration theory.Vehicle model and fluctuating wind load model were established,corresponding vehicle stiffness and damping matrix were educed in the method.A practical cable-stayed bridge dynamic analysis was completed successfully by programming with abovementioned method.The result show that(1)wind load has a great influence on bridge vibration acceleration under low wind velocity;(2)bridge vertical displacement response is influenced evidently by wind load,and the lateral response is controlled by wind load;(3)vehicle vertical dynamic response and acceleration are influenced evidently by wind induced bridge vibration,and the lateral response is controlled by wind load and bridge response.The effect of wind load on vehicle-bridge system dynamic response is remarkable.For other type large span bridges,the method also can be referred for interrelated research.The accuracy of calculation is high enough for practical purposes.