客货混运铁路专线轨道振动分析

Vibration Analysis of Track for Railways with Passenger and Freight Traffic

研究目的：分析客货混运铁路专线客车及货车引起轨道振动的规律。研究方法：通过建立考虑线路随机不平顺的轨道结构连续3层梁模型，论述了运用傅里叶变换法分析轨道结构振动的方法。首先对轨道结构振动方程进行傅里叶变换，求解傅里叶变换域中的振动位移，再通过快速离散傅里叶逆变换得到轨道结构的振动响应。研究结果：分析了客、货列车以不同速度运行时对轨道结构振动的影响。研究表明，在客货混运的铁路专线上，最不利的工况应是货车。在同样的列车速度条件下，货车引起的轨道位移比客车大45％～50％，货车引起的轨道加速度比客车大40％～50％，货车引起的轨道动压力比客车大50％～60％。研究结论：客货混运铁路专线比客运专线和货运专线更易损坏，建设客、货分离的铁路专线是有效的解决方法。

Research purposes： Vibration rules of the track induced by passenger and freight trains for railways with passenger and freight traffic are investigated. Research methods： By means of establishing the continuous elastic 3 layer beam model for track structure with random irregularity of track vertical profile, method of analyzing track vibration by Fourier transform technique is presented. First, the vibration equations of the track structure are transformed by Fourier transform. The vibration displacements in Fourier transform domain are solved with this transformed equation. Then, the vibration responses of the track structure are obtained by performing inverse Fast Fourier Transform. Research results：Influences of different speeds of passenger and freight trains on track vibration are investigated. The studies show that the worst situation is from the freight trains on railways with passenger and freight traffic. The track displacement and the track acceleration as well as the track dynamic pressure resulted from freight traffic are 45% - 50% , 40% -50% and 50% -60% respectively larger than those from the passenger trains when both passenger and freight trains travel at the same speed. Research conclusions：h is easier to be damaged for railways with mixed passenger and freight traffic compared with passenger or freight dedicated railways. Construction of passenger and freight dedicated railways is an effective solution.