中文摘要：

提出时间相关多维有色噪声形式的轨道不平顺激励下列车-桥梁耦合系统协方差响应的时域递推方法。用白噪声滤波法生成轨道不平顺有色噪声过程，在宽频带内识别滤波器参数以同时实现滤波成型和波长截断功能。提出基于高阶Pade近似的累次时滞系统，以实现列车多轮对下轨道不平顺激励的大时滞再现；再结合成型滤波器构造列车下轨道不平顺激励的一致白噪声模型。建立列车-桥梁垂向振动的状态方程，将其与激励模型联立得到一致白噪声激励下的列车-桥梁扩阶状态方程。将方差递推法推广到时变系统，求解列车-桥梁系统的随机振动。分析结果与Monte Carlo模拟法符合良好，表明了方法的正确性。

英文摘要：

A time domain covariance method for the train - bridge vertical stochastic vibration excited by the time - correlated multidimensional nonwhite noise rail irregularity was proposed. The parameter identification of the shape filter producing the nonwhite rail irregularity was carried out in a wide frequency range to realize the shape filtering and the wavelength truncation together. A stepwise time - delay system based on the high order Pade approximation was proposed to simulate the large time - delay excitations under railway trains. The authors combine the shape filter and time - delay system to construct the rail irregularity model with uniform white noise input. The state - space equation of train - bridge vertical vibration was derived, and was integrated with the excitation model to obtain the expanded order train - bridge - excitation state - space equation with uniform white noise disturbance. By extending the recursive covariance method to time- variant system, the covariance response of train- bridge- excitation system was obtained. Numerical results coincide with the Monte Carlo simulation. This indicats the correctness of the method.