大跨独塔斜拉桥拉索梁端锚固区抗疲劳性能  

Fatigue Performance of Anchorage Zone for Long-Span Single Pylon Cable-Stayed Bridge

作　　者：卫星[1] 强士中[1] 

机构地区：[1]西南交通大学土木工程学院,四川成都610031

出　　处：《西南交通大学学报》2011年第6期940-945,共6页Journal of Southwest Jiaotong University

基　　金：铁道部科技开发计划资助项目(2008G029-F);西部交通建设科技项目(200431822317)

摘　　要：为探讨扁平钢箱梁斜拉桥拉索梁端新式锚固结构的疲劳性能,根据锚拉板与主梁的不同连接方式,分析、比较了锚拉板与箱梁外腹板连接和锚拉板与箱梁顶板连接时不同的受力特点及传力路径.用ANSYS有限元软件对锚拉板与箱梁外腹板连接的锚固结构进行了数值模拟,以确定锚固结构的应力分布规律及应力集中的重点部位;在数值分析的基础上,采用足尺模型对拉索梁端锚固区进行了疲劳试验.结合有限元分析和疲劳试验结果,对桥梁设计寿命期内新式锚拉板式锚固结构连接焊缝的抗疲劳性能进行了研究.结果表明:拉索梁端锚固结构板件间连接焊缝的疲劳强度满足设计要求;锚拉板与箱梁外腹板焊接的连接方式降低了应力集中程度,提高了构造细节的疲劳等级,改善了结构的抗疲劳性能.In order to investigate the fatigue performance of a new cable-to-girder anchorage in a cable-stayed bridge with steel box girder, different force transfer paths and mechanic behaviors of two types of anchorages connecting anchor-plate with web of box girder or anchor-plate with top plate of box girder were analyzed for different joint structures between anchor-plate and main girder. Software ANSYS was used to the simulation of anchorage zone to obtain the distribution and concentration degree of stresses. Fatigue test of a full-scale model for the anchorage zone was designed and carried out. By combining simulation analysis with experiment results, fatigue performance of connect welds in the new anchorage system under cyclic load was investigated. Theoretical and experimental results show that fatigue strength of the new anchorage system can meet the need of design. Connecting anchor-plate with web of box girder makes stress concentration reduce, the allowable fatigue stress of weld details increase and the fatigue performance of anchorage zone be improved.

关 键 词：斜拉桥 拉索梁端锚固 疲劳试验 应力集中 数值模拟 

分 类 号：U447.27[建筑科学—桥梁与隧道工程]