复合轨枕无砟轨道疲劳试验研究

复合轨枕无砟轨道是一种新型轨枕无砟轨道结构,通过开展复合轨枕无砟轨道疲劳试验研究其疲劳性能。试验建立复合轨枕无砟轨道实尺模型并对其施加300万次疲劳荷载,观察轨道各部件在疲劳加载前后的伤损情况,测试疲劳加载前后钢轨、复合轨枕、道床板相对位移变化、轨距变化和道床板受力变化。试验结果发现:无砟轨道及其各部件在疲劳试验中均未出现疲劳损伤;轨道结构部件位移在加载前期略有波动,后逐渐减小并趋于稳定,道床板受力满足规范要求。研究结果表明:复合轨枕无砟轨道具有一定耐久性,为其进一步推广和应用奠定了基础。

Experimental Investigation of Fatigue Performance of Composite Sleeper Ballastless Track

The composite sleeper ballastless track is a new sleeper ballastless track structure. The fatigue performance of the composite sleeper ballastless track is studied through fatigue test. A full-scale model is established and subjected to fatigue loading of 3 million times in the fatigue test. The damage of each component of the track before and after the fatigue loading is observed. The change of relative displacement of the rail,composite sleeper and track bed,and the change of the track gauge as well as the change of the track bed stress before and after the fatigue loading are also examined. The experimental results show that no fatigue damage occurs in the composite sleeper ballastless track or in its components during the fatigue test. The displacement of each component of the track slightly fluctuates during the former loading stage and gradually decreases and stabilizes in the later loading stage. The stress of the bed slab meets the requirements of relevant specifications. This research results confirm the durability of the composite sleeper ballastless track, and provide a basis for further promotion and application of the composite sleeper ballastless track.