摘要
区间线路钢轨若发生磨耗将会对弹性波传播产生影响,继而影响弹性波对伤损的识别。采用现场试验,验证半解析有限元方法的正确性;基于该理论方法,对五种不同垂直磨耗量的钢轨求解得到频散曲线,结合波结构对比分析了磨耗后钢轨的频散特性;以群速度变化为指标分析了对垂直磨耗敏感和不敏感的波结构特征,并仿真进行验证。研究表明:在不同垂直磨耗条件下,同一频率附近发生频散曲线相交或偏转的频率随着垂直磨耗量增大而增大,而曲线相交或偏转处的相速度随着垂直磨耗量增大而减小;非敏感波模式主要通过轨腰和轨底传播,而敏感波模式主要通过轨头或全断面传播;轨头垂向振动波模式对钢轨垂直磨耗敏感,选择该波模式进行钢轨缺陷检测需要考虑钢轨磨耗的影响。
If the rail wear occurs in the main line, which can affect the elastic wave propagation and further influence the elastic wave identification of the damage. The semi-analytical finite element method is verified by field tests. Based on the theoretical method, the dispersion curves of five types rails with different vertical wear rates are obtained, and the dispersion characteristics of the rails after wear are compared with the wave structures. The wave structure characteristics that are sensitive and insensitive to vertical wear are analyzed based on the variation of group velocity, and verified by simulation. The results show that the frequency of intersecting or deflection of dispersion curves near the same frequency increases with the increase of vertical wear under different vertical wear conditions, while the phase velocity at the intersecting or deflection of the curves is opposite. The insensitive wave mode propagates mainly through the rail waist and the rail bottom, while the sensitive wave mode propagates mainly through the rail head or the full section. The simulation results show that the vertical vibration wave mode of rail head is sensitive to rail vertical wear, and the influence of rail wear should be considered when selecting this wave mode to detect rail defects.
作者
陈嵘
江文强
李浩然
徐井芒
胡辰阳
田雨虹
CHEN Rong;JIANG Wenqiang;LI Haoran;XU Jingmang;HU Chenyang;TIAN Yuhong(Key Laboratory of High-Speed Railway Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031;Chengdu Yijian Engineering Consulting Agency Co.,Ltd.,Chengdu 610074)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2021年第18期15-22,共8页
Journal of Mechanical Engineering
基金
国家自然科学基金(51978586,51778542,U1734207)
四川省科技支撑计划重点研发(2019YFG0283)资助项目。
关键词
磨耗钢轨
弹性波
半解析有限元
频散特性
波结构
worn rail
elastic wave
semi-analytical finite element method
dispersion characteristics
wave structures
