断索对大跨斜拉桥加劲梁内力的影响分析  

Analysis on the internal force of stiffening girder of long-span cable-stayed bridges to a cable loss

作　　者：张建[1] 杨德灿[1] 舒鹏 ZHANG Jian;YANG De-can;SHU Peng(Department of Road and Bridge Engineering,Wuhan University of Technology,Wuhan 430063,China;CCCC Second Highway Consultants Co.,Ltd.,Wuhan 430056,China)

机构地区：[1]武汉理工大学道路与桥梁工程系,湖北武汉430063 [2]中交第二公路勘察设计研究院有限公司,湖北武汉430056

出　　处：《交通科学与工程》2019年第4期47-51,62,共6页Journal of Transport Science and Engineering

摘　　要：针对斜拉桥的斜拉索在运营期间受到环境和荷载因素的影响会断裂这一极端情况,建立斜拉桥的有限元模型,并对索力进行了优化。根据主桥结构总体布局和构造特点,模拟5种断索工况,对每种工况建立相应的时程函数并进行了动力分析,得到5种工况下结构的动力响应结果。研究结果表明:断索对断裂斜拉索锚固点附近加劲梁的影响比较大,而对于远离断索位置的影响相对较小;断索对跨中加劲梁位移的影响最为显著,而对于靠近辅助墩位置的影响很小;靠近跨中合龙段斜拉索断裂加劲梁弯矩的影响最为显著,而靠近桥塔位置的斜拉索失效对加劲梁弯矩的影响最小。That a cable-stayed bridge in service is under the influence of environment and load factors can lead to a cable fracture.For the extreme situation of cable breakage,a finite element model of a cable-stayed bridge was established and the cable force was optimized.According to the overall layout and structural characteristics of the bridge structure,five kinds of cable loss conditions were simulated.In order to carry out the dynamic analysis for each working condition,the corresponding time-history functions were established.The results show that sudden failure of a stay has a great influence on the main beam near the anchorage point of the fracture cable,but the influence on the main beam which is away from the breaked cable would be small.The fault cable has the most significant effect on the displacement of the main beam in the midspan,but has little influence on the position near the auxiliary pier.For the main beam bending moment of the cable-stayed bridge,the most significant effect appeared near the closure section of the middle span,but the least was near the bridge tower.

关 键 词：断索 斜拉桥 弯矩变化 时程函数 动力分析 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]