大跨径钢箱梁斜拉桥合理成桥索力的优化  

Optimization of Bridge-Completing Cable Force in Cable-Stayed Bridge with Long-Span Steel Box Girder

作　　者：祁超[1] 李元松[1] 杨恒[1] 周小龙[1] 

机构地区：[1]武汉工程大学资源与土木工程学院,湖北武汉430074

出　　处：《武汉工程大学学报》2017年第5期477-481,共5页Journal of Wuhan Institute of Technology

基　　金：武汉工程大学研究生创新基金(CX2016037)

摘　　要：依据影响矩阵调值原理,提出以结构整体弯矩最小为目标,关键节点的位移为约束条件的斜拉桥索力优化方法.首先应用Midas/Civil中"未知荷载系数"功能计算满足特定约束条件的最佳荷载系数,并求出拉索初拉力.然后将系数矩阵与弯矩信息导入Excel中,定义目标函数与约束条件,求出初步优化索力,最后将所得初步索力重新代入Midas/Civil模型中,进行局部微调得最终优化索力.将此方法用于某斜拉桥方案分析,结果表明,优化前后,主梁弯矩减小36%,主塔弯矩减小70%,主梁竖向最大位移减小51%,主塔水平最大位移减小74%,且索力分布均匀,线形更为平顺.To optimize the cable forces in the cable-stayed bridges, we adopted the key nodal displacement as constraint conditions to minimize the bending moment of overall structure. Firstly, the optimized load factor and the initial force of the cable were calculated in Midas/Civil model. Secondly, the coefficient matrix and bending moment data were imported into Excel to define a target function and constraint conditions for the initial cable force. Finally, the optimized cable force was obtained by locally adjusting the initial cable force in Midas/Civil model. The results from analyzing a case of cable-stayed bridge show that the bending moment and maximum vertical displacement of the girder, bending moment and maximum horizontal displacement of the main tower decrease by 36%, 51%, 70% and 74% respectively. The cable force evenly distributes, and the alignment of cable-stayed bridge becomes smoother after optimization.

关 键 词：斜拉桥 索力优化 未知荷载系数 影响矩阵 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]