高速铁路钢轨轨端不平顺劣化原因分析

Reasons Analysis for the Deterioration of Irregularity of High-speed Railway Rail Ends

针对高速铁路个别线路出现的钢轨轨端低塌不平顺劣化问题,现场测试了高速铁路有砟、无砟轨道钢轨轨端平直度,并利用仿真手段,从轮轨接触特性和道床沉降分析钢轨轨端不平顺劣化原因。结果表明:有砟轨道线路钢轨轨端不平顺劣化相对明显且更快,无砟轨道线路钢轨轨端不平顺变化相对稳定;不平顺幅值越大,磨耗及道床沉降越大,与低塌量0.1 mm相比,低塌量0.3 mm时磨耗指数增大18%,道床沉降量增加5%,轨面疲劳指数变化极小;现场测试低塌位置的钢轨磨耗明显大于正常位置、轨面硬度相当,轨道几何高低不平顺幅值增大明显,高速铁路钢轨轨端不平顺劣化主要与钢轨磨耗及道床沉降有关。

In response to the problem of deterioration of rail end irregularityon of individual high-speed railway lines,an investigation was conducted on the changes in rail end flatness under the structural conditions of ballasted and ballastless tracks in high-speed railway.Simulation methods were used to analyze the deterioration reasons for irregularity of rail ends from the perspective of wheel rail contact characteristics and track bed settlement.The results show that the degradation of rail end irregularity on ballasted track lines is relatively significant and faster,while the variation of rail end smoothness on ballastless track lines is relatively stable.The larger the irregularity amplitude,the greater the wear and ballast settlement.Compared with the amplitude of 0.1 mm,the wear index increases by 18%and the ballast settlement increases by 5%at the amplitude of 0.3 mm,and the fatigue index of rail surface changes very little.The rail wear at the irregularity position is obviously larger than that at the normal position,the rail surface hardness is equivalent,and the amplitude of track geometric irregularity increases obviously.The deterioration of rail end irregularity of high-speed railway is mainly related to rail wear and ballast bed settlement.