不同索径拉索风雨激励稳定性影响试验研究

Experimental Study on Aaerodynamic Stability of Rainwind Induced Vibration of Stay Cables of Different Diameters

摘要:

在实验室条件下采用人工模拟降雨成功重现了两种直径拉索的风雨激振现象，系统研究了风速、雨强、结构阻尼比等参数对风雨激振的影响以及螺旋线对拉索振动的抑制作用.试验表明，不同折算风速下拉索大幅振动的机理存在一定差异：在较高折算风速下拉索振动更类似限幅的准驰振振动；在低折算风速下拉索的振动与尾流中的低频涡关系更密切，即是一种涡致振动.

Abstract:

Rainwind induced vibration of cables is a type of vibration with large amplitude and low frequency. The phenomenon of rainwind induced vibration of cables of two different diameters is successfully reproduced under simulated raining condition through wind tunnel test. The effects of several main factors on the characteristics of rainwind vibration and spiraled wires countermeasure for mitigation of the vibration are investigated. The results indicate that the mechanism of vibrations with different reduced velocities is different. Vibration with high reduced velocity is more like a type of galloping, while vibration with low reduced velocity is more related to vortexinduced vibration.