摘要
为研究钢-混组合梁抗风性能及风致振动的控制措施,以某拟建公路斜拉桥为研究对象,通过1:50缩尺比节段模型风洞试验,研究该主梁断面在0.8%的阻尼比下的涡振性能,以及改变结构阻尼比、加装气动措施对结构抗风性能的影响。研究结果表明:均匀流场下,该钢-混组合梁在-3°和+3°风攻角下,均会发生较大幅度的竖向及扭转涡振,共振风速约为20 m/s,П型主梁的钝体外型和小高宽比是导致主梁抗风性能较弱的主要原因。增大结构阻尼比能显著抑制涡振,且阻尼比增大到1.5%时涡振振幅可满足规范要求;设置2道水平翼板能够有效控制主梁在-3°和+3°风攻角下的涡振振幅,但会明显提高0°风攻角下涡振振幅。设置2道水平翼板和上中央稳定板的组合措施可以对3个攻角下的涡振振幅进行有效控制。
To investigate the vortex-induced vibration(VIV)performance and provide reasonable aerodynamic optimization measures of steel-concrete composite beam,the wind tunnel tests of the beam section model with a scale of 1/50 was conducted based on a cable-stayed bridge located in southern China.First,the vortex-induced vibration performance of the beam section was studied experimentally under the damping ratio of 0.8%.Then,the influences of both changing damping ratio and the addition of various aerodynamic optimization measures were investigated.The results indicate that the vortex-induced resonance occurred near the wind speed of 20 m/s with the wind attack angle of-3°and+3°.This could be attributed to the bluff-body shape and small aspect ratio of the П shaped beam.Increasing structural damping ratio could significantly decrease the VIV amplitude.The VIV amplitude would satisfy the code requirement when damping ratio increased to 1.5%.Two outside horizontal stabilizers installed at each edge of the beam could effectively control the VIV amplitude with the wind attack angle of-3°and+3°,but would significantly increase the VIV amplitude with the wind attack angle of 0°.The combined measure with two outside horizontal stabilizers and one vertical stabilizer in the upper middle of the beam could effectively control the VIV for three different wind attack angles.
作者
方国强
杨鸥
FANG Guoqiang;YANG Ou(CCCC Highway Consultants Co.,Ltd.,Beijing 100088,China;College of Civil Engineering,Hunan University,Changsha 410082,China)
出处
《铁道科学与工程学报》
CAS
CSCD
北大核心
2020年第9期2303-2310,共8页
Journal of Railway Science and Engineering
基金
国家重点研发计划项目(2019YFC1511101)
国家自然科学基金面上资助项目(51578229)。
关键词
斜拉桥
气动特性
涡激振动
气动控制
风洞试验
cable-stayed bridge
aerodynamic characteristics
vortex-induced vibration
aerodynamic control
wind tunnel test
作者简介
通信作者:杨鸥(1981-),男,湖南永州人,副教授,博士,从事桥梁工程研究,E-mail:ouyanghnu@hnu.edu.cn。
