小曲线钢轨滚动接触疲劳及车轴疲劳寿命分析

Analysis of Rolling Contact Fatigue of Small Curved Rails and Fatigue Life of Car Axles

为探究小半径曲线上钢轨滚动接触疲劳伤损规律及车轴寿命,文章基于车辆系统动力学模型,对小半径曲线钢轨磨耗计算分析得到钢轨疲劳数据模型。针对小半径曲线的钢轨整个损伤过程进行滚动接触疲劳分析,同时也基于有限元分析简单预测CRH3型动车组在疲劳伤损的钢轨上运行时车轴的疲劳寿命。研究结果显示:(1)在小半径曲线曲中点处外轨主要体现轨距角处的侧磨,内轨主要体现轨顶处的垂磨,且外轨的滚动接触应力和损伤与内轨有显著差异;(2)轮对进行静强度分析得到车轴上轮座压装处应力最大;(3)结合车轴应力和载荷谱对车轴疲劳寿命进行预测,计算发现预测寿命约为11.8 a,车轴在已经产生疲劳磨损的线路上运行时寿命会大大缩减。

In order to investigate the law of rail rolling contact fatigue damage and axle life on small radius curve,the rail fatigue data model was obtained by calculating and analyzing the rail wear on small radius curve based on the established vehicle system dynamics model.The rolling contact fatigue analysis is carried out for the whole damage process of the rail with small radius curve,and the fatigue life of the axle of CRH3 EMU running on the fatigue damaged rail is simply predicted based on the finite element analysis.The conclusions are as follows:(1)At the midpoint of the small radius curve,the outer rail mainly reflects the side wear at the gauge angle,and the inner rail mainly reflects the vertical wear at the top of the rail,and the rolling contact stress and damage of the out-er rail are significantly different from that of the inner rail.(2)The static strength analysis of the wheel set shows that the stress on the the wheel seat on the axle is the largest.(3)Combined with the axle stress and load spectrum,the ax-le fatigue life is predicted,and it is found that the predicted life is about 11.8 a.The life of an axle will be greatly re-duced when running on the line that has already experienced fatigue wear.