基于车体低频横向晃动分析的60N钢轨打磨限值研究

Research on 60N Rail Grinding Limit Based on Carbody Low Frequency Lateral Shaking Analysis

为解决国内部分服役动车组在运营过程中产生车体低频横向晃动问题(以下简称“晃车”),提高车体平稳性和旅客乘坐的舒适性,基于对部分晃车区段(打磨目标为60N钢轨的高速铁路干线)开展跟踪调研与测试的基础上,对比工务系统打磨后左右轨对称情况下,不同偏差值的钢轨廓形对应车体低频横向晃动的差异;并结合动力学仿真软件研究不同偏差值的钢轨廓形对于晃车现象的影响,找出打磨目标为60N钢轨的合理打磨限值并提出相应的打磨措施与建议。结果表明:晃车区段左右股钢轨工作边相较于打磨目标廓形60N钢轨存在过打磨导致等效锥度过小,是造成动车组晃车的重要原因;以车体横向振动加速度、车体横向晃动主频和轮轨匹配等效锥度等值为主要依据,提出60N钢轨在横坐标15 mm处的负偏差为0.1 mm时,会出现晃车现象,建议工务系统以60N钢轨为目标廓形时,按照正偏差打磨,打磨值宜按+0.1 mm控制。

In order to solve the problem of low-frequency lateral body shaking(hereinafter referred to as"car swing")during the operation of some domestic EMUs in service and to improve the stability of the body and the comfort of passengers,the difference between the rail profile with different deviation values corresponding to the low-frequency lateral swing of the car body under the symmetrical situation of the left and right rails after the grinding by the maintenance department is compared based on the part of the shaking section(the grinding target is the high-speed railway main line with steel rails)and the follow-up investigation and testing.The influence of the deviation value of the rail profile on the wobble phenomenon is studied with dynamic simulation software to find out the reasonable grinding limit for the 60N rail,and put forward the corresponding grinding measures and suggestions.The results show that the working side of the left and right steel rails in the swing section is over-grinded compared to the target profile of 60N rail,resulting in excessive small equivalent cone,which is the very reason for the shaking of the EMU.It is proposed that when the negative deviation of the 60N rail at 15 mm on the abscissa is 0.1 mm,vehicle shaking will occur on account of vehicle body lateral vibration,the main frequency of vehicle body lateral shaking and the equivalent taper of wheel and rail matching.It is recommended that the maintenance department should control the grinding value at+0.1 mm according to the positive deviation for 60N rail as the target profile.