基于吸气的流线型箱梁涡振主动流动控制试验研究  

Experimental Study on Active Flow Control of Vortex-Induced Vibration of Streamlined Box Girder Based on Suction

作　　者：李春光 毛禹 颜虎斌 韩艳 LI Chun-guang;MAO Yu;YAN Hu-bin;HAN Yan(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114

出　　处：《桥梁建设》2022年第4期95-102,共8页Bridge Construction

基　　金：国家自然科学基金项目(51978087,51822803);湖南省自然科学基金项目(2020JJ14607)。

摘　　要：为提高流线型箱梁涡激振动性能,以某主跨为808 m的流线型钢箱梁悬索桥为背景,提出一种普遍适用于流线型箱梁的基于吸气的涡振主动流动抑制措施,即在主梁上、下游相应气孔进行吸气,从而对桥梁展向风场进行干扰,避免涡脱产生,从而削弱涡振振幅。对1∶50缩尺比的刚性节段模型进行风洞试验,设置不同主动吸气气孔参数,对最不利攻角下的主梁涡振响应进行研究。结果表明:主梁原断面在+5°攻角下竖弯及扭转位移响应均超过规范限值;基于吸气的涡振主动流动控制措施对流线型箱梁的涡振区间及振幅影响明显;下腹板吸气、吸气速率10 m/s能够完全抑制竖弯涡振的产生,抑振效果理想;上腹板吸气对扭转涡振的抑制效果更加明显;上游下腹板吸气气孔间距2.5 m、吸气速率5 m/s可将竖弯及扭转位移响应控制在规范限值内。A suspension bridge with a main span of 808 m and with stiffening girder consisting of streamlined steel boxes is taken as a case to study the measures to suppress the vortex-induced vibration of streamlined box girder.An active flow control method based on suction that is widely applicable to the streamlined box girder is proposed,namely to suck air from the stipulated upstream and downstream holes in the main stiffening girder,so as to interfere the wind fields along bridge length,and in turn preventing the occurrence of vortex shedding and weakening the amplitude of vortex-induced vibration.A 1∶50 scale rigid segmental model was prepared for the wind tunnel test,with different parameters of active air suction holes,the vortex-induced vibration of stiffening girder at the most unfavorable angle of attack was studied.It is shown that at+5°angle of attack,the vertical bending and torsional displacement of the original cross-section of stiffening girder all exceed the limits in the codes.The active flow control measure based on suction can disturb the range and amplitude of vortex-induced vibration,with distinctive effect.Sucking air from holes in lower webs and with a sucking speed of 10 m/s,the vibration suppression effect is satisfactory,and the vertical vortex-induced vibration is completely suppressed.While sucking air from holes in upper webs,the torsional vibration can be significantly suppressed.When the air suction holes in the upstream lower webs are spaced at 2.5 m,with a sucking speed of 5 m/s,the vertical bending and torsional response can be controlled within the limit range suggested in the codes.

关 键 词：悬索桥 流线型箱梁 涡振性能 抑振措施 主动吸气 流动控制 节段模型 风洞试验 

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]