铁道建筑

有砟轨道大型养路机械维修作业中,捣固的主要动作是向枕底推送道砟并使道床密实。研究捣固镐插入的深度、速度、振动频率等捣固参数对大型养路机械作业效果的影响,对于提高大型养路机械作业效率、延长有砟道床服役年限具有重要意义。基于大型养路机械捣固镐结构和轨道结构建立了精细化捣固作业离散元仿真模型,采用多体动力学几何外形和离散单元分别对捣固镐与道砟颗粒的运动状态进行模拟,并通过试验对模型进行了验证。在不同的插镐速度和深度工况下模拟捣固作业过程,以道砟受到的压力、总动能、平均角速度和增加数量作为捣固效果的评价因素,研究了各工况的捣固作业效果。研究结果表明:在其他作业参数相同的工况下,插镐速度最优值为0.5 m/s,插镐深度最优值为90 mm。

In the maintenance of heavy-duty maintenance machinery in ballast track,the main action of tamping is to push ballast to the bottom of sleeper and make the ballast bed compact.It is of great significance to study the influence of tamping parameters such as the depth,speed and vibration frequency of tamping pick on the operation effect of heavyduty maintenance machinery,so as to improve the operation efficiency of heavy-duty maintenance machinery and extend the service life of ballast bed.Based on the tamping pick structure and track structure of heavy-duty maintenance machinery,the discrete element simulation model of fine tamping operation was established.The movement state of tamping pick and ballast particles was simulated by multi-body dynamic geometry and discrete element respectively,and the model was verified by experiments.The process of tamping operation was simulated under conditions of different pick-inserting speed and depth.Taking the pressure,total kinetic energy,average angular velocity and increased quantity of ballast particles as the evaluation factors of tamping effect,the tamping effect of different working condition was studied.The results show that optimal value of the pick-inserting speed and pick-inserting depth is 0.5 m/s and90 mm respectively with the same other operation parameters.