斜拉索的风雨振动及其控制是目前国内外研究的热点问题之一。其中,阻尼器减振技术得到了广泛的应用,但是,对于阻尼器的一些非理想因素如阻尼器刚度的影响,尚缺乏研究。本文对斜拉索附加带刚度的阻尼器的模态阻尼比进行了分析,通过分析复频率的变化,在阻尼器安装点距拉索锚固点长度与拉索长度之比远远小于1的假设下,得到了考虑刚度影响的拉索阻尼器的模态阻尼比的近似解析解。该近似解析解与数值计算得到的精确解对比吻合良好。对于斜拉索减振,与忽略刚度影响的阻尼器类似,带刚度的阻尼器同样存在着通用设计优化曲线。阻尼器所带有的刚度将显著的减小拉索.阻尼器系统所能获得的最大模态阻尼比,而所对应的阻尼器最优阻尼值将增大。
Wind/rain-induced stay cable vibration and its mitigation have gained many researchers, attention recently. As the mechanism of wind/rain-induced vibration is not clear yet, a damper is usualiy used to suppress the vibration; however, it is need to study the effect of some non-ideal factors of damper, such as damper stiffness, which influences the performance of damper. An approximate optimal design formula for a viscous damper attached to a stay cable considering its stiffness was given by using an analyticall formulation for complex eigenvalue problem, assuming that the ratio of damper installation length to cable length is much smaller than 1. The approximate formula was verified by the accurate results directly calculated from the analytical formulation. The study shows that the stiffness of damper would reduce the maximum attainable modal damping, and the optimum damping coefficient would become larger. Similar to a damper without stiffness. An universal design curve of a damper with stiffness exists also.