铁路工务维修小车动力学分析及安全评估
Dynamics Analysis and Safety Assessment of Railway Works Maintenance Trolley

为评估铁路工务维修小车运行安全性，本文利用多体动力学仿真软件UM，建立了小车的动力学仿真分析模型，分析了小车的运动稳定性，研究了小车在曲线轨道上惰行、驱动以及制动条件下的轮轨走行状态，统计最大值的轮轴横向力、脱轨系数和轮重减载率等指标来判断其安全性。研究结果表明：小车非线性临界速度为37 km/h，因此在最高运行速度20 km/h的情况下，不会出现失稳的现象；小车以0~20 km/h速度范围内通过曲线线路时，各动力学指标都是随速度的增加呈增大的趋势，与安全指标作对比，都在安全范围内，但是由于小车重量较轻，轮重减载率对速度变化较为敏感，最大值十分接近安全限值。现场作业时，小车最高速度不应超过20 km/h，进一步提速尤其会恶化其减载安全性。
To evaluate the running safety of track maintenance vehicle, the multi-body dynamics simulation software UM is used to establish the dynamic model of the vehicle. The motion stability is analyzed. Under the idling, driving and braking conditions, the wheel-rail running state on the curved track is investigated. The maximum values of wheelset lateral force, derailment coefficient and wheel load reduction rate are statistically analyzed to research its running safety. The research results show that, the critical speed of the vehicle can reach 37 km/h, which means the motion instability phenomenon will not occur in the vehicle running below 20 km/h. For the vehicle passing through curved track at speed of 0~20 km/h, the values of dynamic indices increase with the speed increasing. But the security indices can be kept within the security limit. However, the wheel load reduction rate is sensitive to the speed change due to the lower weight of the vehicle. Its maximum value is closed to the safety limit. In the field operation, the top speed should not exceed 20 km/h, otherwise the rise in speed could deteriorate the load reduction safety.