摘要
为研究纵向肋条气动措施对斜拉索风雨激振现象的抑振机制,首先,建立可用于分析带有运动水线的不同气动外形斜拉索的风雨激振理论模型;然后,推导耦合的水膜运动方程和拉索振动方程;最后,采用该理论模型系统分析带有不同个数纵向肋条的斜拉索的振动响应、水膜形态特征以及拉索表面气动升力和阻力的变化特性等。结果表明:纵向肋条会阻碍上水线的形成,通过增加拉索表面的纵向肋条个数,可降低拉索发生风雨激振的风险;当拉索沿环向布置12根纵向肋条时,水线运动的主频已远远偏离拉索的固有频率,在保证风阻系数小的同时降低拉索的横风向振幅,减振效果最佳。
This paper is presented in order to study the mitigation mechanism of longitudinal ribs on rainwind-induced vibration.Firstly,a theoretical vibration model of stay cables with kinetic rivulet which could be used for different aerodynamic shapes was established.Then the coupled water film oscillation and cable vibration equations were deduced.Finally,the theoretical model was used to study cable vibration response,water film features and changes of aerodynamic lifts and drags of stay cables with different longitudinal ribs.The results show that longitudinal ribs could suppress the formation of upper rivulet,and the increase of longitudinal ribs number could reduce the occurrence of rain-wind-induced vibration;the mitigation effect will be the best when the stay cable is installed with 12 longitudinal ribs since the dominant frequency of water film will deviate from the inherent frequency of stay cables,thus reducing the amplitude of crosswind while ensuring the drag coefficient is small and the amplitude of stay cable is decreased,the mitigation effect is the best.
作者
毕继红
乔浩玥
关健
王剑
BI Jihong;QIAO Haoyue;GUAN Jian;WANG Jian(School of Civil Engineering,Tianjin University,Tianjin 300350,China;Key Laboratory of Coast Civil Structure Safety,Ministry of Education,Tianjin 300072,China;School of Civil Engineering,Tianjin Chengjian University,Tianjin 300384,China;Key Laboratory of Soft Soil Characteristic and Engineering Environment of Tianjin,Tianjin 300384,China)
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2019年第6期134-139,共6页
China Safety Science Journal
基金
天津市自然科学基金资助(18JCYBJC90800)
关键词
风雨激振
数值模拟
上水线
气动力
纵向肋条
rain-wind-induced vibration
numerical simulation
upper rivulet
aerodynamic forces
longitudinal ribs
