摘要
研究目的:分离式双叠合梁因结构简洁、力学性能优越,在桥梁工程中应用广泛,但其断面钝化易发生涡激振动,在大攻角下更为显著。本文通过1/45比例尺节段模型风洞试验,测试分离式双叠合梁断面在大攻角下的涡激振动性能,研究阻尼比的影响并讨论涡振诱因,进一步提出封闭双梁开口、分段封闭外侧栏杆、三种导流板等单一和组合气动措施并进行测试。研究结论:(1)该分离式双叠合梁断面在0°、-3°、±5°和±7°风攻角下均会发生大幅的竖向涡振,且振幅随攻角的增大而增大;(2)降低阻尼比会增加竖向涡振幅值并激发扭转涡振,阻尼比在0.3%~1.0%的范围内对竖向涡振的影响较扭转涡振更大;(3)分段封闭外侧栏杆可以控制+5°和+7°风攻角的涡振响应,导流板可以控制0°和-3°风攻角的涡振响应;(4)组合气动措施结合了两种措施的优势,且对-5°风攻角的控制效率达到了81%,但是对-7°风攻角的控制有限;(5)本研究结果可为大攻角下分离式双叠合梁涡激振动气动措施优化提供参考和借鉴。
Research purposes:Separated double composite beams are widely used in bridge engineering due to their simple structure and superior mechanical properties.However,its passivation section is prone to vortex-induced vibra⁃tion(VIV),which is more significant at large wind attack angle.The VIV performance of the section was tested by the sectional model wind tunnel test of 1/45 scale.The influence of damping ratio and the cause of VIV were discussed.Fur⁃thermore,single and combined aerodynamic measures such as closed double girder openings,segmented closed outer handrails,and three types of deflectors were proposed and tested.Research conclusions:(1)The separated double composite beam experiences significant vertical VIV at 0°,-3°,±5°and±7°wind attack angles,and the amplitude increases with the increase of the attack angle.(2)Reducing the damp⁃ing ratio can increase the amplitude of vertical VIV and excite torsional VIV.The damping ratio within the range of 0.3%to 1.0%has a greater impact on vertical VIV than torsional VIV.(3)The segmented closed outer handrails can control the VIV response at+5°and+7°wind attack angles,and the guiding plates can control the VIV response at 0°and−3°wind attack angles(.4)The combined aerodynamic measures integrate the advantages of the two measures,and the con⁃trol efficiency at-5°wind attack angle has reached 81%,but the control at-7°wind attack angle is limited(.5)The re⁃sults of this study can provide reference and guidance for optimizing aerodynamic measures for VIV of separated double composite beams at high angles of attack.
作者
李松涛
刘占辉
商聪杰
王聪
宋随弟
鲍玉龙
LI Songtao;LIU Zhanhui;SHANG Congjie;WANG Cong;SONG Suidi;BAO Yulong(China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu,Sichuan 610031,China;Southwest Jiaotong University,Chengdu,Sichuan 610031,China;State Key Laboratory of Bridge Intelligent and Green Construction,Southwest Jiaotong University,Chengdu,Sichuan 611756,China)
出处
《铁道工程学报》
北大核心
2025年第10期46-51,共6页
Journal of Railway Engineering Society
基金
国家自然科学基金项目(52388102,U21A20154)
中央高校基本科研业务费专项资金资助项目(2682024ZTPY020,2682025GH012)
四川省自然科学基金资助项目(2025ZNSFSC0402)。
关键词
分离式双叠合梁
气动措施
风洞试验
涡激振动
大攻角
separated double composite beam
aerodynamic measure
wind tunnel test
vortex-induced vibration
large wind attack angle
