开口断面钢-混结合梁悬索桥颤振特性及颤振形态研究  

Flutter Characteristics and Modes of Suspension Bridge with Open Steel-Concrete Composite Stiffening Girder

作　　者：华旭刚[1] 陈鲁深 李瑜 王甜 陈政清[1] HUA Xugang;CHEN Lushen;LI Yu;WANG Tian;CHEN Zhengqing(Wind Engineering Research Center,Hunan University,Changsha 410082,China;Hunan Communications Planning,Survey and Design Institute Co.,Ltd.,Changsha 410200,China)

机构地区：[1]湖南大学风工程试验研究中心,湖南长沙410082 [2]湖南省交通规划勘察设计院有限公司,湖南长沙410200

出　　处：《桥梁建设》2024年第1期23-30,共8页Bridge Construction

基　　金：国家自然科学基金项目(52025082)。

摘　　要：为准确评估开口断面双边箱钢-混结合梁悬索桥颤振性能和多模态参与效应,以典型的钢-混结合梁悬索桥——怀化洞庭溪沅水特大桥为背景,开展风洞模型试验及数值分析。制作加劲梁节段缩尺模型并进行风洞试验,测试原桥梁结构的颤振性能,分析调整阻尼比、采用气动措施及结构措施对结构颤振特性的影响,采用三维和二维两种颤振分析方法分析设置中央扣结构的颤振模态及多模态参与效应。结果表明:该钢-混结合梁悬索桥存在较明显的颤振起振点,且颤振是以扭转为主的弯扭耦合振动,同时其扭转和竖向振动存在较大的相位差(相差近180°);节段模型风洞试验与三维和二维颤振分析一致得到设置中央扣后,频率较高的正对称扭转模态先于反对称模态发生颤振,且三维与二维颤振分析结果相差不大。The bridge crossing the Dongting stream that flows into the Yuanshui River in Hunan Province,also known as the Dongtingxi Yuanshui River Bridge,is used as a case to study the flutter characteristics and multimode participation effects of the suspension bridge with stiffening girders composed of double open steel edge boxes and concrete panels.A scale-down sectional model of the stiffening girder was fabricated for the wind tunnel test to investigate the flutter performance of the original bridge structure as well as ways to improve the flutter critical wind velocity,including adjusting the structural damping ratios,optimizing the aerodynamic shapes of the stiffening girder and adding central buckle in the stiffening girder.The flutter modes and multimode participation effects of the stiffening girder with central buckles were three-dimensionally and two-dimensionally simulated.It is shown that the flutter critical wind velocity in the case bridge is high,and the flutter is registered mainly as the torsion-dominated torsional-vertical resonances,with big phase difference between torsion and vertical vibrations(about 180°).When the stiffening girder is fitted with central buckles,the symmetrical torsional modes with higher frequencies were observed before the occurrence of asymmetrical modes in the wind tunnel test,which was in agreement with the results of the wind tunnel test,and there was minimal difference between the 3D and 2D flutter analyses.

关 键 词：悬索桥 钢-混结合梁 开口断面 中央扣 颤振性能 颤振形态 风洞试验 数值分析 

分 类 号：U448.25[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]