钢轨焊缝不平顺对扣件弹条动应力的影响分析  

Effect of Rail Weld Irregularities on Dynamic Stress of Fastening Spring Clip

作　　者：刘小军[1] 赵春发[1] 张徐[1] 

机构地区：[1]西南交通大学牵引动力国家重点实验室,四川成都610031

出　　处：《西南科技大学学报》2015年第4期20-24,共5页Journal of Southwest University of Science and Technology

基　　金：国家自然科学基金(51578469;51478399);牵引动力国家重点实验室自主研究课题(2015TPL_T12)

摘　　要：建立弹条Ⅱ型扣件有限元模型,开展了不同波深、不同波长焊缝不平顺条件下弹条动应力分析。研究结果表明:扣件安装到位后其力学性能指标符合铺设安装规范要求,弹条后弯肢内侧表层出现轻微局部塑性屈服,建立的扣件有限元模型能较准确模拟弹条应力状态;有焊缝不平顺时弹条动应力幅值较平顺线路显著增大,会加快弹条疲劳伤损;弹条动应力幅值和轮对通过瞬间突变应力幅值均随焊缝不平顺波深增大而线性增大,随不平顺波长减小先缓慢增加,波长小于0.2 m以后急剧增大。A finite element model（ FEM） of the spring clip type II fastening has been established,and dynamic stress analysis of the spring clip has been carried out considering various wavelength and wave depth of rail weld irregularities. Numerical results show that mechanical performance indexes of the fastening meet the installation requirement when it is installed in right place,the inside surface layer of spring clip at rear bent part appears slight local plastic yielding. It means the FEM model of fastening can simulate correctly stress states of the spring clip. Comparing to the smooth rail,dynamic stress amplitude of the spring clip increases remarkably when the rail have the weld irregularity,and it will accelerate fatigue damage of the spring clip. Both dynamic stress amplitude of spring clip and the abrupt stress amplitude increases linearly with the wave depth of weld irregularity; in addition,they increase slowly with the decrease of the wavelength of the weld irregularity firstly,then increase rapidly since the wavelength is smaller than 0. 2 m.

关 键 词：弹条扣件 动应力 轨道不平顺 非线性接触 有限元法 

分 类 号：U213.2[交通运输工程—道路与铁道工程]