基于载荷因子和牵引系数的钢轨踏面隐伤形成机理及预测研究  

Study on the Formation Mechanism and Prediction of Rail Tread Squats Based on Load Factor and Traction Coefficient

作　　者：李晓宇[1] 习年生[1] 胥红敏[1] 

机构地区：[1]中国铁道科学研究院铁道科学技术研究发展中心,北京100081

出　　处：《中国铁道科学》2012年第B08期12-16,共5页China Railway Science

基　　金：铁道部科技研究开发计划项目（2011T009）;中国铁道科学研究院铁道科学技术研究发展中心项目（2012YF16）

摘　　要：基于安定曲线，确定载荷因子和牵引系数是钢轨踏面隐伤形成的重要影响因素。采用有限元分析软件ABAQUS建立钢轨的有限元模型，并以广深线车辆-轨道耦合动力学计算得到的轮轨接触力及接触斑为该模型的输入，对钢轨踏面特别是轮轨接触部位及其附近区域的应力场进行仿真。结果表明：V型裂纹在轨头内部的扩展使得裂纹所在区域在轮轨力的作用下产生凹陷，形成钢轨踏面隐伤；载荷因子为2～3、牵引系数≥0．36是钢轨踏面形成隐伤的线路工况条件。应用该条件对我国典型线路是否可能产生钢轨踏面隐伤进行预测，广深线、浙赣线满足钢轨踏面葫生隐伤的条件，而大秦线则不可能产生隐伤，这与实测结果一致，表明基于载荷因子和牵引系数的钢轨踏面隐伤预测方法是可行的。Load factor and traction coefficient are confirmed to be two important influencing factors for the formation of rail tread squats based on the analysis of shakedown curve. Finite element analysis software ABAQUS was adopted to establish the finite element model of rail. Wheel-rail contact force and contact spot, which were obtained by the vehicle-track coupling dynamics calculations of Guangzhou-Shenzhen Line, were used for the input of the model. The stress fields of rail tread, especially the wheel-rail contact position and nearby areas were then simulated. Results show that V type cracks can develop within rail head and then make the area of crack growth sink below the surrounding region under the influence of wheel-rail force. Rail tread squats are formed consequently. Specifically, the load case of formation of rail tread squats is that there must be an appropriate load factor between 2 and 3, and also a traction coefficient greater than or equal to 0. 36. This condition has been applied to the typical railway lines in China to pre- dict whether rail tread squats may happen or not. The prediction is that Guangzhou-Shenzhen Line and Zhejiang-Jiangxi Line satisfy the condition and rail tread squats may occur, while Datong-Qinhuangdao Line is unlikely to form rail tread squats. This is consistent with the measured results. The prediction method of rail tread squats based on load factor and traction coefficient is proved to be feasible.

关 键 词：钢轨踏面 隐伤 机理 预测 安定曲线 载荷因子 牵引系数 

分 类 号：U213.42[交通运输工程—道路与铁道工程]