大胜关长江大桥轻轨托架与整体节点连接疲劳及稳定性研究  

Research on the Fatigue and Stability of Connection between Light Rail Bracket and Integral Node of the Dashengguan Yangtze River Bridge

作　　者：王霆 肖林[2] 岳奕町 李小珍[2] WANG Ting;XIAO Lin;YUE Yiting;LI Xiaozhen(Nanjing Metro Construction Co.,Ltd.,Nanjing 210017,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]南京地铁建设有限责任公司,南京210017 [2]西南交通大学土木工程学院,成都610031

出　　处：《铁道标准设计》2021年第5期97-100,共4页Railway Standard Design

基　　金：国家自然科学基金项目(52078424);中国中铁股份有限公司科技研究开发计划项目(2015-重大-10)。

摘　　要：大胜关长江大桥在主桁架整体节点外侧悬挑托架承载轻轨交通。针对轻轨托架与整体节点连接的疲劳性能及托架结构稳定性,设计缩尺模型进行疲劳加载和测试,对其疲劳性能进行评估;建立轻轨托架与节点的三维非线性有限元模型,分析托架结构的稳定性。疲劳试验结果表明,在设计生命周期等效疲劳荷载作用下,结构疲劳易损区域发生应力重分布现象,但轻轨托架与整体节点连接构造不会发生疲劳破坏;有限元分析结果表明,托架腹板是结构失稳的薄弱环节,在考虑制造缺陷等情况下,极限承载力是设计荷载的2.877倍,具有足够的安全系数。The overhanging bracket outside the integral node of the main truss of the Dashengguan Yangtze River Bridge bears the light rail transit. In order to investigate the fatigue performance and stability of the connection, the bracket’s scale model is built and tested with sinusoidal fatigue load, the structural strains are obtained and stresses are analyzed. The stability coefficient of the bracket and the integral node is researched using the non-linear finite element analysis. The fatigue test results show that a certain level of fatigue damage occurs in some areas of the joint, which may lead to stress redistribution;but fatigue failure will not occur during design life cycle. The results of finite element analysis show that the web of bracket is the weak point of structural stability, but the web’s ultimate bearing capacity is 2.877 times of the design load in consideration of manufacturing defects, which justifies its sufficient safety factor.

关 键 词：整体节点 轻轨托架 疲劳试验 稳定性 有限元分析 铁路桥梁 

分 类 号：U441.4[建筑科学—桥梁与隧道工程] U448.36[交通运输工程—道路与铁道工程]