摘要
大跨度悬索桥吊索频率低、阻尼小,极易在风荷载作用下发生大幅振动。为比较研究平行钢丝和钢丝绳2类吊索尾流致振特性的差异,以深中通道伶仃洋大桥四索股吊索为工程背景进行了系统的试验研究。首先,设计并制作了2类吊索的气弹模型,并进行了模型动力参数识别;然后,进行了2类吊索的气弹模型测振风洞试验,比较研究了风速和风攻角等参数对2类四索股吊索尾流致振的影响规律;最后,进行了多种抑振措施(包括分隔架、调谐质量阻尼器、辅助索和增加结构阻尼等)对上述2类四索股吊索风致振动的抑振效果研究。结果表明:2类吊索发生尾流致振的最不利攻角均为75°,并在多个工况下发生碰索现象,吊索主要为一阶振动,轨迹呈顺时针椭圆;相较于平行钢丝吊索,钢丝绳吊索发生尾流致振的风攻角范围更大;采用等间距3个分隔架可有效抑制吊索相对振动,在此基础上,增加辅助索措施可有效抑制吊索的整体振动。
Long-span suspension bridge hangers are prone to large amplitude vibration under wind load because of their low frequency and low damping.In order to compare the difference of wake-induced vibration characteristics between parallel wire strand(PWS)and wire rope(WR)hangers,a systematic experimental investigation was carried out on the four-cable hangers based on the Lingdingyang Bridge.First,three-dimensional aeroelastic models of two types of hangers were designed and manufactured,and the dynamic parameters of the test models were identified.Then,wind tunnel tests on the aeroelastic test model were conducted to obtain the wind-induced vibration of the two types of four-cable hangers.The influence of wind velocity and wind attack angles on the wake-induced vibration of two types of four-cable hangers was investigated.Finally,several different countermeasures to reduce the wind-induced vibration of the hangers(including spacers,tuned mass damper,cross-ties and increasing damping ratio)were performed.The results show that the most disadvantageous attack angle for wake-induced vibration of both hangers is 75°,and cable collision phenomenon is observed at several working conditions.The first-order vibration of hangers are mainly occurred,with a clockwise elliptical trajectory.Compared with PWS hangers,the range of wind attack angles of WR hangers with wake-induced vibration are larger.The wake-induced vibration of the hangers can be effectively suppressed by adding three equally spaced spacers.On this basis,wind-induced vibration can be effectively suppressed by the countermeasure of adding cross-ties.
作者
李寿英
李啸宇
邓羊晨
宋神友
陈焕勇
陈政清
LI Shou-ying;LI Xiao-yu;DENG Yang-chen;SONG Shen-you;CHEN Huan-yong;CHEN Zheng-qing(Key Laboratory for Wind and Bridge Engineering of Hunan Province,Hunan University,Changsha 410082,Hunan,China;School of Civil Engineering and Architecture,East China Jiaotong University,Nanchang 330013,Jiangxi,China;Shenzhen-Zhongshan Link Administration Center,Zhongshan 528449,Guangdong,China)
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2024年第7期147-156,共10页
China Journal of Highway and Transport
基金
国家自然科学基金项目(51578234)
湖南省自然科学基金项目(2021JJ40070)。
关键词
桥梁工程
悬索桥吊索
风洞试验
尾流致振
三维气弹模型
振动控制
bridge engineering
suspension bridge hangers
wind tunnel tests
wake-induced vibration
three-dimensional aeroelastic models
vibration control
