斜拉索-调谐质量阻尼器系统复模态分析

摘要

针对斜拉索减振常用黏滞阻尼器的一些不利因素如安装位置、刚度、耦合运动等,提出斜拉索-调谐质量阻尼器（TMD）系统的减振模型,运用复模态方法分析得到以超越方程形式表达的系统自由振动阻尼特性的解析形式,采用数值方法求得系统最优模态阻尼比和阻尼器最优设计参数的近似解析解.结果表明：斜拉索振动的TMD减振策略能有效克服常用的理想阻尼器安装位置在拉索端部的局限,新的TMD设计参数优化方法同时考虑了TMD系统刚度、质量、阻尼等参数对减振系统模态阻尼比的影响,是适合工程应用的斜拉索减振模型.%The adverse factors such as damper position and damper,stiffness,and couple movement et al.are not avoidable in existing bridge cable mitigation models.In this study,A stay cable with a Tuned mass damper（TMD） installed is proposed for vibrate reduction.Damping properties in the free vibration of the system were extracted by complex-mode analysis technique.Explicit analytical approximation was obtained by numerical method.Result shows that the proposed TMD system damping stay cables vibration strategy could effectively overcome the common position limitations of idealized damper.The new optimization method taking account a thorough effect of the TMD system stiffness,mass,damping and other parameters on the damping ratio of modal parameters in cable vibrating reduction model.Hence the new model matches well with the actual occurrence in bridge engineering.