轨道系统钢轨振动衰减率动力测试研究

摘要

Research purposes:Decay rate (DR)is closely related to the dynamic damping properties of the track, which is used to describe the rail vibration propagation behavior with distance alone the track.Experimental study was conducted to compare DR between Egg system track structure and the standard track form with DTVI2 fastening system. Furthermore,the reasons and control measures of the rail corrugation occurred on Beijing metro were also analyzed. Research conclusions:(1)The DR of Egg system track structure was higher in the frequency range (f >400Hz)than which on DTVI2 track structure.(2)The DR on Egg system track structure was less than 0.1dB /m in the frequency range of 160 ~250Hz,implying that the pronounced train /track resonance was not able to be damped in this frequency range,which was identified closely related to a track form specific rail corrugation occurred on the section of Egg system on Beijing metro.(3 )Adjusting the rail frequency response behavior to avoid the resonance peak,together with improving the system dynamic damping to suppress the rail vibration,were effective measures to control the abnormal corrugation development.(4)The results of the paper can provide references to control the rail corrugation.%研究目的：钢轨振动衰减率是轨道结构动力分析的重要内容，可反映振动沿钢轨纵向传播的特性。本文采用试验的方法，对比分析剪切型减振器、DTVI2扣件两种轨道结构型式下的钢轨振动衰减率，并进一步分析北京地铁特殊钢轨波磨的成因及整治措施。　　研究结论：（1）在大于400 Hz 频率范围内，剪切型减振器扣件比 DTVI2扣件具有更大的振动衰减率；（2）剪切型减振器扣件在160～250 Hz 频段的振动衰减率较低，大部分低于0．1 dB／m，在该频段不能提供足够的阻尼抑制轮轨相互作用引起的剧烈振动，这是钢轨异常波磨快速发展的主要原因之一；（3）针对性地调节轨道系统振动频率特性以避开轨道共振峰值点，并提高系统动态阻尼抑制钢轨振动，是有效整治异常波磨发展的重要改进措施；（4）本研究成果可为整治北京地铁异常钢轨波磨提供依据。