重载铁路钢轨轨底坡对轮轨接触行为的影响

Effect of Rail Cant on Wheel-rail Contact Behavior of Heavy Haul Railway

从轮轨接触几何关系和接触力学特性出发,分析了不同轨底坡下重载铁路机车JM3型踏面、货车LM型踏面与CHN75钢轨的匹配状态及其对滚动接触行为的影响。结果表明:轨底坡1/40条件下2种车轮踏面与CHN75钢轨匹配时轮轨接触点对都分布在钢轨顶面与车轮踏面中心的接触区,磨耗分布较均匀,而且轨底坡的变化对于轮缘磨耗影响不大;2种车轮踏面的纵向、横向蠕滑力均随轨底坡减小而增大;LM型踏面轨底坡取1/20时接触斑面积最大,最大法向接触应力最小,钢轨的磨耗和疲劳损伤程度最轻;JM3型踏面轨底坡取1/40时接触斑面积变化较小,不会出现法向接触应力激增的情况,有利于铁路长期保持安全稳定的运行状态。

Based on the wheel-rail contact geometry relation and contact mechanical characteristics,the matching state of JM3 tread of heavy haul railway locomotive and LM tread of freight car with CHN75 rail and its influence on rolling contact behavior were analyzed.The results show that when the rail cant is 1/40 and the two wheel treads match with CHN75 rail,the wheel-rail contact point pairs are distributed in the contact area between the rail top surface and the wheel tread center,and the wear distribution is more uniform,and the change of rail cant has little effect on the wheel flange wear.The longitudinal and transverse creep forces of the two wheel treads increase with the decrease of the rail cant.When the LM tread rail cant is 1/20,the contact spot area is the largest,the maximum normal contact stress is the minimum,and the rail wear and fatigue damage are the least.When the JM3 tread rail cant is 1/40,the change of contact spot area is small,and there will be no sharp increase of normal contact stress,which is conducive to the longterm safe and stable operation of the railway.