高锰钢辙叉振动特性的数值研究

Numerical study on the vibration characteristics of the high manganese steel crossing

通过模态分析得到了高锰钢辙叉-轨枕系统的固有频率和振型特征,并讨论了道床刚度和轨枕材料对高锰钢辙叉振动特性的影响。数值结果表明:高锰钢辙叉的模态形状包括垂向弯曲、横向弯曲、扭转三种形式;横向弯曲和扭转两种振动形态总是同时出现;其变形以垂向弯曲为主,且固有频率随道床刚度的增加单调增大;导致高锰钢辙叉疲劳失效的外部激励主要是轮轨冲击力的高频力(大于500Hz)。在低频率(小于400Hz)范围内,轨枕材料分别取橡木和高性能混凝土时各阶固有频率非常接近,最大相差值不超过50Hz;在高频(大于400Hz)范围内,二者结果有所差别,最大相差值超过100Hz。

The vibration characteristics of the high manganese steel crossing are analyzed,and the natural frequencies and mode shapes are obtained.The influences of the railway ballast stiffness and ties material properties on the vibration characteristics are examined.The numerical results reveal that mode shapes of the high manganese steel crossing include vertical bending,transverse bending and torsion.Transverse bending and torsion always appear simultaneously,while vertical bending is the main deformation of the high manganese steel crossing.The natural frequencies increase monotonically with increasing ballast stiffness.The high frequency wheel-crossing impact loads(higher than 500Hz) are the main external driving force which leads to failure of the high manganese steel crossing.The natural frequencies for the two kinds of tie materials(oak and high-performance concrete) cannot be distinguished within low frequency range(less than 400Hz),whereas at high frequencies(more than 400Hz),they are slightly different.