槽形钢箱梁涡振性能及抑振措施试验研究  

Experimental Study on Vortex-Induced Vibration Performance and Vibration Suppression Measures of Trough-Shaped Steel Box Girders

作　　者：封周权[1] 戴金元 陈诗璇 华旭刚[1] FENG Zhouquan;DAI Jinyuan;CHEN Shixuan;HUA Xugang(Key Laboratory for Wind and Bridge Engineering of Hunan Province,Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学风工程与桥梁工程湖南省重点实验室,湖南长沙410082

出　　处：《世界桥梁》2024年第3期83-89,共7页World Bridges

基　　金：长沙市政府采购研究项目(CSCG-202107060066)。

摘　　要：为提高槽形钢箱梁桥的抗风性能,对槽形钢箱梁的涡振性能及抑振措施进行试验研究。以某人行景观桥槽形钢箱梁为背景,通过主梁节段模型风洞试验,研究+3°、0°、-3°风攻角下均匀流与紊流风场中槽形钢箱梁的涡振性能,分析交替封闭栏杆、将栏杆楔形扶手改为圆形扶手、提高阻尼比等措施的抑振效果。结果表明:原槽形钢箱梁断面涡振性能不满足规范要求,均匀流风场中,3个风攻角下均出现了超限的竖弯涡振,+3°和-3°风攻角下出现了不同程度的扭转涡振,最不利风攻角为-3°;紊流风场中,最不利风攻角下原断面竖弯涡振振幅降低了23%,未见明显扭转涡振;楔形扶手栏杆交替封闭使结构竖弯涡振振幅增大,主梁涡振性能降低;单独改变栏杆扶手形状为圆形对主梁涡振性能影响不大,在此基础上交替封闭栏杆能够有效抑制主梁涡振;提高结构阻尼比能有效抑制主梁涡振,阻尼比为7‰时,主梁竖弯涡振振幅可降至规范限值的一半左右。To enhance the wind resistance of a bridge with a trough-shaped steel box girder,experimental studies were conducted to investigate the vortex-induced vibration(VIV)performance and vibration suppression measures of the girder.The research focused on a pedestrian landscape bridge′s trough-shaped steel box girder,examining its VIV performance under uniform and turbulent wind conditions at+3°,0°,and-3°wind attack angles through sectional wind tunnel tests.Additionally,the study analyzed the effects of vibration suppression measures,including alternately closing railings,changing wedge handrails to circular handrails,and increasing the damping ratio.Results revealed that the original trough-shaped steel box girder section did not meet design code requirements.Under uniform wind flow,vertical bending VIV exceeding limits occurred at all three wind attack angles,with torsional vortex vibration observed at+3°and-3°wind attack angles,with the most unfavorable angle being-3°.In turbulent wind fields,the vertical bending VIV amplitude of the original section decreased by 23%at the most unfavorable wind attack angles,and no significant torsional VIV was observed.The alternately closed railings with wedge-shaped handrails resulted in an increase in the vertical bending VIV amplitude of the girder and degraded the overall VIV performance of the girder.Changing the handrail shape to circular had minimal impact on the VIV performance,but when combined with alternately closed railings,it effectively suppressed VIV.Furthermore,increasing the structural damping ratio significantly suppressed VIV.At a damping ratio of 7‰,the maximum vertical bending VIV amplitude of the girder was reduced to about half the limit value.

关 键 词：人行桥 槽形钢箱梁 风致振动 涡振性能 抑振措施 扶手形状 阻尼比 风洞试验 

分 类 号：U448.213[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]