时速140 km地铁中等减振轨道钢轨振动特征分析

Rail Vibration Characteristics Analysis of Medium Vibration Reduction Rails in 140 km/h Subway

结合车辆-轨道耦合动力学,分析时速140 km地铁中等减振轨道钢轨振动特征。在Timoshenko梁理论基础上,利用编程实现可考虑钢轨剪切及扭转变形的车辆-轨道耦合模型的构建,并对时速140 km地铁钢轨加速度幅值、钢轨加速度振级、钢轨位移进行仿真计算。结果表明,时速140 km地铁中等减振轨道钢轨加速度峰值约为624.2 m/s2,较时速120 km、80 km地铁增幅明显;时速140 km地铁中等减振轨道加速度主频较时速80 km地铁明显提高,且主频振级也略有增加;钢轨位移受列车速度变化影响较小。建议时速140 km地铁铺轨过程中注意扣件调节,使其前三阶固有频率尽量避开钢轨振动主频。

In combination with the vehicle-track coupling dynamics,the vibration characteristics of the medium-damped rail of the 140 km/h subway are analyzed.On the basis of Timoshenko beam theory,programming is used to establish the vehicle-track coupling model which can consider the shear and torsional deformation of the rail,and the simulation calculation is carried out on the acceleration amplitude of the rail,the acceleration level of the rail,and the displacement of the rail.The results show that the peak acceleration of the medium-damped rail at speed 140 km/h is about 624.2 m/s^2,which is a significant increase from the rail at speed 80 km/h and 120 km/h.The main frequency of the medium-damped track acceleration of the subway at speed 140 km/h is significantly higher than that of the subway at speed 80 km/h,and the main frequency vibration level has also increased slightly;change in subway speed has little effect on displacement of rail.It is recommended to pay attention to adjust the fasteners during the process of laying the subway at a speed of 140 km/h so that the first three natural frequencies can avoid the main frequency of rail vibration as much as possible.