列车荷载引起路基振动研究分析

The Research on the Subgrade Vibration Caused by Train Load

为了研究地基特性和轨道结构对列车振动荷载作用下地基振动问题,通过无限元边界与有限元边界相结合的有限元分析方法进行模型建立,把路堤高度、列车速度、阻尼系数、振动频率及轨道抗弯刚度因素考虑在内.结果表明,无限元边界与有限元边界相结合的有限元计算方法可以有效反映出地基振动效果,由列车荷载引起的地基振动响应随着路堤高度增加而减小;速度增加地基振动响应相应增加,并且低速与高速情况相应情况变化很大;列车低速时,轨道刚度对地基振动影响较小,相反高速时轨道刚度对振动响应影响较大;当列车速度低于剪切波速时阻尼系数改变对振动影响较小,高于剪切波速时,阻尼系数增大路堤周围地基振动水平明显减小;随着列车荷载振动频率增加,地基振动响应变化较小,但是具有减小趋势.

In order to study the foundation vibration problem about features and track struc- ture under the action of the train vibration load, it based on combining the finite element anal- ysis method with the embankment height, the train speed, the damping coefficient, vibration frequency and track bending stiffness factors taken into account. The result show that com- bined with finite element boundary of infinite element boundary finite element method can effectively reflect the effect of the foundation vibration; the foundation vibration response caused by the train load decreased as the embankment height; As the speed is increased, ground vibration response increased, and the low speed and high speed of the corresponding situation changed a lot; when the train is running in low speed, the track stiffness has less affected on foundation vibration, while running at high speed, the track stiffness has great influence on the vibration response; When the speed of the train is lower than the shear wave velocity, the changes of vibration damping coefficient is small, while higher than the shear wave velocity, As the damping coefficient increasing, the ground vibration level was decreased; With the increase of the train load vibration frequency, the response of ground vibration change~ small, but it has a decreasing trend.