地铁道岔尖轨早期伤损分析

近年来国内地铁线路建设和开通呈井喷形势,但是新开通线路尖轨出现早期异常伤损现象较为普遍,给列车安全运行、线路运营带来隐患。通过对地铁新建线路道岔尖轨早期出现伤损的调研,深入研究伤损形貌与特征,结合轮轨关系、道岔转辙器结构特性、运动特性、尖轨线型、尖轨轨顶坡、轨道弹性等影响因素进行分析,判断地铁尖轨的破损型属于接触疲劳伤损,得出产生轨头接触疲劳伤损的主要原因是轮轨接触应力过大,提出一致性新车轮的运营条件引起的接触应力集中,是产生伤损的主要原因的结论,并提出改善轮轨关系、改善运营条件、提高材料性能、加强维护保养等延缓地铁道岔早期伤损的措施。

Horizontal Crack Damage of Explosive Hardening High-Manganese-Steel Composite Frog

The construction and opening of domestic subway lines have increased in recent years. However, early abnormal damage of switch rails in a newly opened line is common and causes hidden dangers to the safe operation of the trains and the lines. Through an investigation of the early damage of switch rails in new subway lines, we determine that the damage type of the subway switch rail is contact fatigue damage. The damage features and characteristics are studied in depth and combined with the wheel-rail relationship, structural characteristics, running characteristics, switch rail type, and top slope of the turnout. Influencing factors such as the track elasticity are analyzed. The main reason for the occurrence of rail head contact fatigue damage is that the wheel-rail contact stress is too large, and the operating conditions of a consistent new wheel are the main reason for the damage. The following measures to delay early damage to a subway is therefore proposed: to improve the wheel-rail relationship, to improve the operating conditions, to improve the material performance, and to enhance maintenance.