高耸结构TMD接触非线性阻尼振动控制研究

Vibration control of high-rising buildings with TMD considering contact non-linear damping effect

调谐质量阻尼器(TMD)能有效地控制高层建筑结构的风致振动,而TMD子结构往往将产生过大的冲程,且由于荷载不确定性决定其冲程也是不可确定的,故必须进行限位设计。鉴于此,对TMD的限位控制进行研究,提出了大阻尼TMD系统、开关阻尼限位控制和离位阻尼限位控制三种不同的限位策略。以广州新中轴线电视塔结构为分析模型,结合TMD系统在运动过程中的8个工作状态,给出了在考虑开关阻尼限位控制和离位阻尼限位控制两种限位控制策略下系统的运动方程,并进行了风载激励下的数值仿真分析。数值分析的结果表明:不同限位间距时,两种限位工况对系统位移、加速度响应的峰值和均方值控制效果规律不尽相同;对于开关限位控制,当限位距离为TMD最优控制下摆幅的36%时,在控制效果损失约4%的前提下,TMD的摆幅与最优控制下的摆幅相比,减少了约45%;当TMD摆幅相同时,与大阻尼TMD系统相比,其控制效果高8%;离位限位控制对结构加速度峰值有更好的控制效果。恰当地选择限位距离和限位阻尼系数,既能改善风致振动下结构的舒适度,又能减小TMD的摆幅。

It is effective for tuned mass damper(TMD) to reduce vibration response of high buildings under wind excitation,but the displacement of the TMD sub-structure is too much bigger.So it is necessary to design parameters for limit position of TMD in applications.Firstly,the dynamic characteristic of an analysis model,Guangzhou new TV tower that will be one of the highest tower in the world,was introduced.The system equilibrium equations of the two limit cases,on-off damper limit position and OE(off-equilibrium)-damper limit position control strategies,were deduced.Under fluctuating wind excitations the simulations were done.The results showed that the limit position distance is the key point to decide OE or on-off damper control method,which is more effective to control different objectives.When the position distance was about 36% of the classical TMD displacement response,the TMD's displacement response with limit position could be reduced about 45% with only 4% control effect loss.And it is more effective for OE-damper limit postion strategy to control the main structure acceleration peak response.So it was significant to choose right limit distance and damping parameter for designing limit position according to different demands.