初始不平顺与初始弯曲的叠加方式对无缝线路稳定性影响

针对无缝线路稳定性方面的分析,研究线路初始不平顺与初始弹塑性弯曲之间的叠加方式具有重要意义。根据无缝线路稳定性有限元分析理论建立钢轨、扣件、轨枕和道床阻力为一体的轨道框架模型,对于桥上无缝线路由于梁端相对伸缩产生的线路不平顺,分析线路不平顺幅值位置以及各弦测法对应矢度最大值位置与初始弹塑性弯曲的叠加线型对无缝线路稳定性的影响。分析表明:梁端横向伸缩引起的钢轨变形会降低无缝线路的稳定性。建议对于存在初始不平顺的线路,首先采用4 m弦长对线路初始不平顺进行测量,得到最大的矢度对应的位置,然后与钢轨初始弹塑性弯曲最大处相对应进行叠加,最后进行求解,以此作为计算无缝线路稳定性最不利的工况。

Effects of Initial Irregularity and Initial Bending Stacking on the Stability of Continuous Welded Rail

Analysis of the stability of continuous welded rail is conducted to understand the initial track irregularity and initial elastic-plastic bending's superposition. Based on CWR track stability finite element analysis theory,a track framework model is established in perspective of the rail,fastening,sleeper and roadbed resistance to analyze the effects of the track initial irregularity and initial elastic-plastic bending's superposition on the stability of continuous welded rail with respect to the track irregularity produced by beam end relative extension. Analysis shows that the track initial irregularity may reduce track stability.Suggestions for the presence of track initial irregularity are made to use 4m chord to measure the track initial irregularity for the maximum position relating to the vector,and then stack with the rail initial elastic-plastic bending,and the solution is taken as the worst condition of the stability of continuous welded rail.