DT-Ⅲ型扣件系统弹条疲劳特性及优化研究  

Study on fatigue characteristics and optimization of fastener clips of DT-Ⅲ fastener system

作　　者：宋子洋 卢俊[1,2] 胡世斌 陈明明 赵才友[1,2] SONG Ziyang;LU Jun;HU Shibin;CHEN Mingming;ZHAO Caiyou(Key Laboratory of High-speed Railway Engineering,Ministry of Education,Chengdu 610031,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Chongqing Rail Transit(Group)Co.Ltd.,Chongqing 401120,China)

机构地区：[1]高速铁路线路工程教育部重点实验室,四川成都610031 [2]西南交通大学土木工程学院,四川成都610031 [3]重庆市轨道交通(集团)有限公司,重庆401120

出　　处：《中南大学学报（自然科学版）》2021年第10期3623-3635,共13页Journal of Central South University:Science and Technology

基　　金：高速铁路基础研究联合基金资助项目(U1734207);国家自然科学基金资助项目(51978585);四川省应用基础研究项目(2020YJ0214)。

摘　　要：针对DT-Ⅲ型扣件系统弹条断裂的现象,为探究弹条在列车动静荷载下的疲劳失效问题,通过建立精细化有限元模型,分析Ⅲ型弹条的静、动力学响应结果,并提出采用高频弹条和改进绝缘轨距块的方式来改善弹条受力情况,最后通过车辆-轨道耦合模型分析弹条疲劳寿命的变化规律。研究结果表明:高频弹条最大等效应力为1 400 MPa,与普通Ⅲ型弹条相比其最大等效应力及扣压力基本无变化,而最大等效应力位置转移到后拱小圆弧靠近跟端处,前四阶固有频率均增加。随着绝缘阻尼块弹性模量增加和厚度增加,其最大等效应力及扣压力会增大,固有频率变化不大。当波磨波长为40 mm和幅值为0.02 mm时,Ⅲ型弹条振动加速度最大值为212 m/s^(2),而高频弹条仅为127 m/s^(2);Ⅲ型弹条疲劳损伤为4.36×10^(-6),远高于高频弹条的损伤6.86×10^(-7)。在同样工况下,使用阻尼轨距块时弹条损伤相比正常轨距块时也有一定程度降低。Aiming at the fracture phenomenon of the fastener clips of the DT-Ⅲ type fastener system, in order to explore the fatigue failure problem of the fastener clips under the dynamic and static load of the train, the static and dynamic response results of the type Ⅲ fastener clips were analyzed by establishing a refined finite element model(FEM), and the use of high-frequency fastener clips was proposed and the insulation gauge blocks was improved to improve the stress of the fastener clips. Finally, the vehicle-rail coupling model was used to analyze the changes in the fatigue life of the fastener clips. The results show that the maximum equivalent stress of the high-frequency fastener clips is 1 400 MPa. Compared with the ordinary one, the maximum equivalent stress and the buckling pressure are basically unchanged, and the position of the maximum equivalent stress is transferred to the small arc of the rear arch close to the heel. With the increase of the elastic modulus and thickness of the insulation damping block, the maximum equivalent stress and the buckling pressure increase. When the wave milling wavelength is 40 mm and the amplitude is 0.02 mm, the maximum vibration acceleration of Type Ⅲ fastener clips is 212 m/s^(2), while the high frequency fastener clips is only 127 m/s^(2);the fatigue damage of the type Ⅲ elastic clips is 4.36×10^(-6), which is much higher than that of the high-frequency fastener clips bullets(6.86×10^(-7)). Under the same working conditions, the damage of the fastener clips when using the damping gauge block is also reduced to a certain extent compared with the normal gauge block.

关 键 词：扣件系统 高频弹条 绝缘轨距块 有限元模型 轮轨系统 疲劳寿命 

分 类 号：U231[交通运输工程—道路与铁道工程]