基于高速列车作用引起的铁道线路垂向动态响应的研究

研究了在高速列车作用下，由运行质量变化和沿线路方向的弹性基础支撑的非均匀性等所引起的对铁道线路的垂向动态响应。在时域内使用FEA法推导建立了高速列车／线路系统相互作用的运动方程，通过使用数值积分算法，分析了车辆运行速度、移动质量、线路的弹性基础支撑及其非均匀性等参数变化对铁道线路动态性能的影响，通过与通用分析模型结果进行的对比显示了良好的一致性。研究表明轨枕失效区域对钢轨的动态响应影响显著，在非均匀弹性基础支撑上钢轨的变形与移动质量的大小成反比，但在均匀基础支撑上钢轨的变形则与移动质量的大小无关。

Study on Vertical Dynamic Response of Railway Track Induced by Express Trains

The vertical dynamic response of railway track due to changes of the traveling mass and non uniform foundation properties along the track under a high speed moving train is studied. The method based on the finite element analysis is used to develop and set up the governing second order differential equations on the interaction between the express train and track, and a custom program utilizing the Newmark integration algorithm is implemented to solve the equations. The effects of the speed of traveling train, the moving mass, the foundation stiffness and non uniform foundation properties etc. on dynamic performances of railway track have been investigated and analyzed. Comparing with results of the general beam model, the results show good agreement. The conclusions demonstrate that the dynamic response of the rail is more significant over the larger missing tie zones than the foundation properties. As the quantity of mass traveling along the rail increases, the peak deflection of the rail decreases for a linear non uniform foundation; and when the foundation is linear and uniform, the peak deflections are the same with or without the added mass.