摘要
针对中间索面斜拉桥并列拉索的尾流驰振,在驰振基本理论的基础上结合大涡数值模拟方法进行了数值研究。研究首先回顾了驰振的基本理论,进一步利用大涡数值风洞模拟方法获得了横风下并列拉索的静风荷载系数,并分析了不同风攻角时上游索对下游索三分力系数的影响。在驰振判别原则的基础之上开展并列拉索尾流驰振的判别方法和发生风速的研究。结果表明上游拉索不会发现驰振失稳,下游拉索则发生驰振失稳的可能性很高,同时提高拉索结构阻尼比或者改变拉索局部振动频率均能有效地提高尾流驰振发生风速。最后建议并列拉索采用连接器相连的措施以提高拉索局部振动的频率,该措施可以极大地提高拉索尾流驰振稳定性。
The wake galloping of parallel cables of cable stayed bridges with central cable planes was numerically simulated based on fundamental galloping theory and making use of large eddy numerical simulation technique. The galloping theory was reviewed, and the static wind load on parallel cables under transverse wind was obtained by the numerical simulation. The effects of upwind cables on downwind ones were investigated by comparing the three-component coefficients under different wind attack angles. The discrimination rule and onset wind speed of wake galloping of parallel cables were developed. The results show that galloping instability will not happen on upwind cables. But the downwind cables are of great possibility of wake galloping instability. Analysis results also show that increasing the structural damping and local vibration frequencies of parallel cables will effectively improve the onset wind speed of wake galloping. The measure of connecting parallel cables with connectors to increase the local vibration frequencies was suggested and it is proved that this measure can greatly increase the wake galloping stability of parallel cables.
出处
《振动与冲击》
EI
CSCD
北大核心
2013年第10期91-94,共4页
Journal of Vibration and Shock
基金
国家"十一五"科技支撑计划资助项目(2006BAG04B02)
交通运输建设科技项目(2011 318 494 160)
