波磨对轮轨系统动力特性的影响分析

Effect of Rail Corrugation on Dynamic Properties of Wheel-Rail System

针对某地铁曲线路段钢轨波磨频发的问题,现场测量了20处钢轨的波磨,并以该实测的波磨作为激励,利用车辆—轨道耦合动力学模型,研究波磨对轮轨系统动力特性的影响规律。结果表明:该地铁波磨的纵向长度为1.5~3.0m,最大波深为0.2~0.4mm,波长范围在140~200mm,接近或者达到钢轨打磨限值,但是轮轨系统响应并未超限;波磨波深与轮轨垂向力、轮对垂向加速度和钢轨垂向加速度都没有明显的对应关系;波深时变率与钢轨垂向加速度没有明显的对应关系,但与轮轨垂向力和轮对垂向加速度都有较明显的线性对应关系,波磨波深变化快的位置,即波深时变率的峰谷值附近,都对应着轮轨垂向力和轮对垂向加速度的极值。由于波深时变率与轮轨垂向力和轮对垂向加速度之间有明显、一致的线性对应关系,基于波磨波深时变率的钢轨打磨标准比基于波深的打磨标准更加直观和合理。

As rail corrugation occurred frequently in the curve section of a metro,field measurements were carried out on 20 rail sections with corrugations.Themeasured corrugations were used as excitations to study the influence laws of corrugation on the dynamic properties of wheel-rail system by means of vehicle-track coupling dynamic model.Results show that,the longitudinal length of eachcorrugation section for the measured metro ranges from 1.5 to 3.0 m.The maximum wave depth ranges from 0.2 to 0.4 mm and the wave length ranges from 140to 200 mm,which is close to or reaches rail grinding limit.However,the response of wheel-rail system does not exceed the limit.There is no obvious corresponding relation between the wave depth of corrugation and the wheel-rail vertical force,the vertical accelerations of wheelset and rail.There is no obvious corresponding relation between the time-varying rate of wave depth and the vertical accelerations of rail,while there is a more obvious linear corresponding relationbetween the time-varying rate of wave depth and wheel-rail vertical force andthe vertical acceleration of wheelset.The positions where the wave depths of corrugation change quickly,i.e.near the peak and valley values of the time-varying rate of wave depth,all correspond to the extreme values of wheel-rail vertical force and the vertical acceleration of wheelset.Since there is a clear and uniform linear relation between the time-varying rate of wave depth and the wheel-rail vertical force and the vertical acceleration of wheelset,the rail grinding standard based on the time-varying rate of wave depth is more intuitiveand reasonable than the grinding standard based on the wave depth.