摘要
狮子洋大桥为主跨2180 m的双层桥面板桁-箱桁组合钢梁悬索桥,该桥中跨桥面高度处设计基准风速高达48.0 m/s。为确保该超大跨度悬索桥运营阶段的抗风安全性,围绕主梁气动外形优化开展多方案抗风性能比选及风致振动性能评价。结合气象站概率统计模型设计风速和混合气候模式设计风速,确定狮子洋大桥桥位处设计风参数;对5种主梁方案开展主梁节段模型风洞试验,进行主梁方案比选和颤振稳定性气动措施优化、不同扭转阻尼比下涡激共振稳定性评价以及台风气候模式下多模态抖振频域计算。结果表明:桥位设计基本风速取34.9 m/s;颤振稳定性方面,对5种主梁方案,上、下层桥面设置通长纵梁能显著改善主梁断面的气动稳定性,增设桥面底部中央稳定板、封闭下层桥面底部和上、下弦杆风嘴可进一步提升抑振效果;涡激共振响应方面,当扭转阻尼比达到0.32%时,扭转涡激共振基本消失;抖振响应方面,台风下主梁抖振响应显著高于《公路桥梁抗风设计规范》(JTG/T 3360-01—2018)规定的百年重现期内设计风速下抖振响应。推荐主梁方案为上、下层桥面系分别采用正交异性钢桥面板和整体式箱梁的双层桥面板桁-箱桁组合钢梁,其主梁断面可满足颤振、涡激共振和抖振的抗风安全设计要求。
The Shiziyang Bridge is a suspension bridge with a main span of 2180 m.The superstructure consists of two planes of trusses,the connection orthotropic steel deck panels creating an upper deck,and the connection steel boxes forming the lower deck.The design reference wind velocity at the deck of the central span is as high as 48.0 m/s.To ensure the wind resistant safety of the suspension bridge with an extra long main span at the service stage,multiple aerodynamic shape optimization measures for the main girder were compared and the wind-induced vibrations were evaluated.Based on the design wind velocities obtained by the statistical model at the meteorological station and the wind velocities obtained by the mix wind climate,the design wind parameters of the Shiziyang Bridge site were determined.Segmental wind tunnel tests were carried out on five girders with different aerodynamic shapes,focusing on the type selection of the main girder,aerodynamic shape optimization to improve the flutter stability,evaluation of vortex-induced vibration(VIV)stability considering different torsional damping ratios,and the calculation of multi-mode buffeting frequency domains under typhoons.As per the analysis,the design reference wind velocity at the bridge site draws a value of 34.9 m/s.Five aerodynamic shape optimization measures are effective in improving the flutter stability of the bridge structure,including adding full-length stringers in the upper and lower decks to effectively improve the aerodynamic stability of the superstructure,as well as adding central stabilizer plates,closing the bottom of the lower deck,and adding wind fairings at the upper and lower chords can further enhance the vibration suppression effect.When the torsional damping ratio reaches 0.32%,the torsional VIVs almost disappear.The buffeting responses of the bridge in typhoons are more violent than the buffing responses under the design wind velocities with a return period of 100 years in the Wind-Resistant Design Specification for Highway Bridges(JTG/T 3360-01-2018).The recommended design for the Shiziyang Bridge is to use orthotropic steel deck plates for the upper deck and the integral steel boxes for the lower deck,to create a composite superstructure that can meet the requirements of the flutter,VIVs and buffeting resistance safety of the bridge.
作者
赵林
刘鹏
徐军
崔冰
崔巍
ZHAO Lin;LIU Peng;XU Jun;CUI Bing;CUI Wei(State Key Laboratory of Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China;College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Key Laboratory of Transport Industry of Wind Resistant Technology for Bridge Structures,Tongji University,Shanghai 200092,China;CCCC Highway Consultants Co.,Ltd.,Beijing 100088,China)
出处
《桥梁建设》
北大核心
2025年第1期15-23,共9页
Bridge Construction
基金
国家自然科学基金项目(52378527,52008314,52078383)。
关键词
悬索桥
双层桥面板桁-箱桁组合钢梁
台风
风致振动
气动选型
风洞试验
suspension bridge
composite girder with orthotropic steel deck and steel box deck
typhoon
wind-induced vibration
aerodynamic shape optimization
wind tunnel test
