Discrete element method was first used to simulate the dynamic process of train crash to mortar rubble line terminal stopper. The discrete element model of mortar rubble line terminal stopper and longitudinal dynamic model of train were built and the crash process was simulated by data exchange of two models. A sliding accident was taken for example to simulate and analyze the dynamic process of train crash to mortar rubble line terminal stopper. Results showed that the train crashed to the mortar rubble line terminal stopper with the initial velocity of 4. 3 m ? S-1, and the velocity reduced to 3. 96 m ? S-l after crash, indicating that the energy absorbed by the stopper was limited. The soil particle distribution in the stopper wall and the damage of vehicle structure after crash agreed well with accident scene, indicating that the simulation of the crash process was effective. The crash cases with different initial velocity were simulated. Results show that the energy consumption of mortar rubble line terminal stopper, the maximum impact force and the final velocity of train after crash all increase with the increase of initial crash velocity. The linear relationship between the final velocity after crash and the initial crash velocity of the train is obtained by fitting. The maximum allowable crash velocity of mortar rubble terminal stopper is 0. 6504 m ? S-1. When the velocity is lower than it, the mortar rubble line terminal stopper can stop the train from rushing out track.%首次采用离散单元法对列车冲撞浆砌片石式线路终端车挡进行仿真分析.利用建立的浆砌片石式终端车挡离散单元模型和列车纵向动力学模型,通过两模型间的数据交换,实现冲撞过程的仿真.以某次溜车事故为例,对列车冲撞浆砌片石式终端车挡的动态过程进行仿真分析.结果表明:列车以4.3m·s-1的初速度冲撞浆砌片石式线路终端车挡,冲撞后列车的速度降至3.96m·s-1,表明该车挡能够吸收的能量较少；冲撞后车挡墙体中的土壤颗粒分布以及车辆结构的损坏与现场情况吻合程度很好,表明对冲撞过程的仿真模拟是有效的.对不同初速度冲撞工况进行仿真,结果表明,浆砌片石式终端车挡消耗的能量、最大冲击力和列车末速度均随着冲撞初速度的增大而增大；拟合得到列车冲撞末速度与初速度的线性关系,并计算出浆砌片石式终端车挡的最大允许冲撞速度为0.6504m.s-1,当车速低于该速度时,该车挡可以阻止列车冲出轨道.
展开▼
