山区峡谷大跨度斜拉桥施工阶段抖振响应及抗风索减振措施研究  

Buffeting Responses of Long-Span,Valley-Crossing,Cable-Stayed Bridge in Mountainous Area and Application of Wind Cables for Vibration Mitigation

作　　者：张捷[1] 刘小波 杨霄[1] 张天翼 ZHANG Jie;LIU Xiaobo;YANG Xiao;ZHANG Tianyi(Sichuan Road and Bridge Engineering Co.,Ltd.,Chengdu 610071,China;Sichuan Chuanqian Expressway Co.,Ltd.,Chengdu 610503,China;Sichuan Road&Bridge Group Co.,Ltd.,Chengdu 610041,China;Wind Engineering Key Laboratory of Sichuan Province,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]四川路桥桥梁工程有限责任公司,四川成都610071 [2]四川川黔高速公路有限公司,四川成都610503 [3]四川路桥建设集团股份有限公司,四川成都610041 [4]西南交通大学风工程试验研究中心,四川成都610031

出　　处：《世界桥梁》2025年第1期79-87,共9页World Bridges

基　　金：国家自然科学基金项目(52208462);四川省交通运输科技项目(2021-ZL-08)。

摘　　要：为研究山区峡谷大跨度斜拉桥在不同施工状态下的抖振响应特点,以及适用于该类桥梁的抗风索减振措施,以跨越深切峡谷的某大跨度斜拉桥为背景,采用有限元时域分析方法计算该桥在最大双悬臂施工状态、单悬臂中期施工状态和最大单悬臂施工状态下的抖振响应,分析不同布置形式抗风索对抖振响应的抑制作用。结果表明:主梁在最大双悬臂施工状态下梁端竖向抖振位移显著,主要由桥塔顺桥向弯曲引起;单悬臂中期施工状态结构整体刚度提升使得梁端竖向和塔顶顺桥向抖振位移明显降低;最大单悬臂施工状态主梁悬臂段最长,主梁抖振响应较单悬臂中期施工状态显著增大。一端与桥塔承台连接的传统抗风索可大幅降低最大双悬臂状态主梁的竖向抖振位移,最大减小率达55.3%,但对单悬臂施工状态桥梁抖振响应的抑制效果并不明显;当主桥处于最大单悬臂施工状态时,在两侧主梁悬臂端采用交叉连接方式布置的“软连接”抗风索可有效抑制主梁的竖向、横桥向和扭转抖振位移,且减振效果优于平行连接。This study investigates the buffeting response characteristics of long-span cable-stayed bridges crossing valleys in mountainous areas when the bridge was in different construction states,and a method of using wind cables for vibration mitigation is proposed.A long-span cable-stayed bridge crossing a deep valley,is used as a case.Finite element modelling was conducted to analyze the buffeting responses of the bridge in the maximum double-cantilever construction state,halfway single-cantilever construction state,and maximum single-cantilever construction state,and study the buffeting mitigation effects of wind cables arranged in different ways.The results show that the vertical girder-end displacements induced by buffeting in the maximum double-cantilever construction state is significant,which is mainly caused by the longitudinal bending of pylons.At halfway of the single-cantilever construction state,the enhanced overall rigidity of the structure results in the distinct reduction of the girder-end vertical buffeting displacements and the pylon-top longitudinal buffeting displacements.Due to that the cantilever is the longest in the maximum single-cantilever construction state,the buffeting responses are obviously more intense than that in the halfway single-cantilever construction state.The traditional wind cables linked to the pile cap on one end can significantly reduce the vertical buffeting responses of the main girder in the maximum double-cantilever construction state,with a reduction rate reaching 55.3%,but negligible mitigation effect on buffeting responses of the bridge in the single-cantilever construction state.When the bridge is in the maximum single-cantilever construction state,to diagonally arrange the"flexible link"wind cables at the tips of the two main girder cantilevers can effectively suppress the vertical and transverse torsional buffeting displacements,and the vibration mitigation effect is superior to that of the parallel connection.

关 键 词：斜拉桥 山区峡谷 施工状态 抖振响应 抗风索 时域分析 减振措施 有限元法 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U441.3[交通运输工程—道路与铁道工程]