【作者】 晋智斌； 强士中； 李小珍；

【Author】 Jin Zhibin Li Xiaozhen Qiang Shizhong (School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

【机构】 西南交通大学土木工程学院桥梁系；

【摘要】 针对高速列车-桥梁垂向耦合振动系统,考虑桥梁结构参数随机性,提出了时变系统瞬态随机响应的摄动分析方法。建立了车-桥随机结构动力方程并转化为随机状态方程,以便利用转移矩阵进行求解。桥梁结构模态分解时采用对质量归一化的随机模态函数,简化了系统方程且避免了逆矩阵的求导运算。将车-桥随机状态方程系数及状态变量在均值处展开,提出了基于均值摄动法的车-桥时变系统随机瞬态响应的求解方法。数值算例表明,该方法与Monte Carlo模拟法符合良好,也无长期项效应。更多还原

【Abstract】 A perturbation method was proposed to analyze the stochastic response of the train-bridge coupling system with uncertain parameters.The vehicle-bridge stochastic dynamic equation was derived and transformed into a state-space representation which can be efficiently solved by using the state-transition matrix. The bridge’s mode decomposition was performed with respect to the mass normalized stochastic mode coordinates.And this modal transformation can avoid the calculation of the inverse mass matrix’s deviation and simplify the dynamic equation.Expanding coefficients and the state vector of the stochastic equation as their mean and deviation,an improved perturbation algorithm was derived to evaluate the transient stochastic response of the train-bridge stochastic time-variant system.Numerical examples indicate that results of the perturbation algorithm accord well with the Monte Carlo simulation method and no secularity appears.更多还原