千米级斜拉桥扁平钢箱梁的局部力学行为-天津大学期刊中心.PDF

第 43 卷 第 7 期 天 津 大 学 学 报 Vol.43 No.7 2010 年 7 月 Journal of Tianjin University Jul. 2010 ▋ 千米级斜拉桥扁平钢箱梁的局部力学行为 张鹏飞，张启伟 (同济大学桥梁工程系，上海 200092) 摘 要 ：以世界最大跨径斜拉桥苏通长江大桥为工程背景，通过静载试验与全桥整体及箱梁局部有限元数值计算研 究了千米级斜拉桥扁平钢箱梁各主要板件的力学特性．在此基础上，运用子模型法对考虑焊接构造的箱梁局部焊接细 节建立精细有限元模型，分析焊缝周围的应力分布规律，并通过试验加以验证．结果表明 ，扁平钢箱梁剪力滞效应明 显，顶底板纵向应力沿横截面呈不均匀分布，顶板和顶板 U 肋的焊缝周围存在严重的应力集中，是整个钢箱梁疲劳性 能研究的重点部位． 关键词 ：静载试验；应力分布；焊接细节；应力集中 中图分类号：U448.27 文献标志码 ：A 文章编号 ：0493-2137 (2010)07-0593-08 Local Mechanical Behavior of Flat Steel Box Girder for Kilometer-Level Cable-Stayed Bridge ZHANG Peng-fei ，ZHANG Qi-wei (Department of Bridge Engineering ，Tongji University ，Shanghai 200092 ，China) By using static load tests and FEM numerical calculation of the whole bridge and local box girder ，Sutong Abstract ： Yangtze River bridge ，whose span is the longest among the cable-stayed bridges of the world ，was taken as an ex- ample to investigate the mechanical properties of the main parts of the flat steel box girder in kilometer-level cable stayed bridges. On this basis ，a fine finite element model of the welded details in the steel box girder including welded conformation was built with submodel technique to analyze the stress distribution along the weld toe ，which was verified through test. The research results indicate that the transverse shear lag effect of the steel girder is signifi- cant and the longit