钢桥整体节点疲劳性能分析-桥梁与隧道工程专业论文.docxVIP

西南交通大学硕士研究生学位论文 第l页 摘 要 近年来，整体节点在大跨度钢桁梁桥中逐渐被采用。整体节点焊缝密集， 焊缝类型多样，其疲劳强度对整个钢桥的安全至关重要。目前，对于整体节 点疲劳强度的研究还很少。本文采用理论与试验相结合的研究方法，以正在 兴建的重庆菜园坝长江大桥为背景，重点研究了各种构造细节对钢桥整体节 点疲劳强度的影响。 本文首先简要介绍了钢桥疲劳的基本概念，阐述了疲劳强度基本理论， 分柝了影响焊接锅结构疲劳强度的主要因素，比较了各种构造细节的疲劳强 度。然后分析了钢桥整体节点所包含的构造细节，介绍了国内外对这些构造 细节的研究成果，评价了钢桥整体节点的疲劳性能。 在本文的最后，利用有关知识和以往的研究成果，分析了重庆菜园坝长 江大桥整体节点与轨道横梁连接处所包含构造细节的疲劳强度。在此基础 上，通过整体模型疲劳试验和有限元分析，比较了试验结果和理论计算结果。 对试验结果和理论分析结果进行分析评价后，验证了重庆菜园坝长江大桥整 体节点与轨道横梁连接的可靠性。 关键词：整体节点；焊接钢结构；构造细节；疲劳强度  Abstract In the last few years，monolithic joint has been gradually adopted in the long span steel truss bridge．It is the hi曲ly important that we should know the fatigue property of monolithic joint with dense and various welded searn．Presently,there is only a little study about the fatigue property of steel bridge monolithic joint．In this thesis，the study method combining theory calculation with model test is adopted． Based on Chongqing Caiyuanba Yangtze Bridge，it is studied that various structure details impact on the fatigue property ofsteel bridge monolithic joint． First of all，some basic conceptions about fatigue failure of steel bridge are introduced，and some basic theories about fatigue strength are also introduced in this thesis．The main factors causing welded structure fatigue are analyzed．The fatigue strengths of some structure details of welded structure are compared．Secondly,the structure details contained in monolithic joint are analyzed，the research findings about these structure details are introduced，and the fatigue property of steel bridge monolithic joint is evaluated． At last，the fatigue strengths of structure details which are contained in the connection of monolithic joint and track CROSS beam of Chongqing Caiyuanba Yangtze double—deck Bridge are analyzed in this thesis．Based on these，test results and theory results are compared through model fatigue test and finite element analysis．Through analyzing and evaluating，it is proved that the connections of monolithic joint and track cross