基于节段模型试验的悬索桥涡振抑振措施

Mitigation Measures of Vortex-Induced Vibration of Suspension Bridge Based on Section Model Test

为研究大跨度悬索桥涡激振动性能,并提出有效的涡振抑振措施,以某大跨度钢箱梁悬索桥为工程背景,通过1∶20大尺度节段模型风洞试验,在低阻尼下研究了人行道栏杆、检修轨道、导流板对主梁涡激振动性能的影响;通过在检修轨道内侧设置导流板抑制主梁的涡激振动,并基于试验现象探讨了涡激振动发生的机理.研究表明,在检修轨道内侧设置导流板抑制主梁涡激振动的措施使桥梁断面的气动外形更合理,抑振效果好,且结构形式简单,便于工程应用.

In order to investigate the vortex-induced vibration performance of long-span suspension bridges and propose effective mitigation measures,a long-span suspension bridge with steel-box girder was taken as an engineering example.By a section model wind tunnel test with a scale of 1∶20,the effects of railings,maintenance rail and guide vane on the vortex-induced vibration performance of main girder at a low damping were investigated,and the mitigation measure of setting guide vane inside the maintenance rail was applied in bridge engineering.In addition,the mechanism of the vortex-induced vibration was discussed based on the test phenomenon.The research results show that the vortex-induced vibration can be effectively mitigated by the above measure,and the mitigation measure makes the aerodynamic shape of the main girder be more reasonable.Furthermore,the structure for this measure is relatively simple to be convenient for engineering application.