设置非线性黏滞阻尼耗能框架结构等效阻尼及地震作用分析

Equivalent Damp Ratio and Seismic Action Analysis of Energy Dissipation Frame Structure with Nonlinear Viscous Damper

研究了设置非线性黏滞阻尼器框架结构的等效阻尼比及地震作用.构建了多自由度耗能减震框架结构振动方程,基于等效前后结构阻尼耗能总量及各阶振动正则坐标幅值不变原则,建立了耗能结构一阶振型等效阻尼比的解析计算式.在此基础上,利用傅里叶变换法,给出了高阶振型等效阻尼比计算式.最后以设置非线性黏滞阻尼器的10层钢筋混凝土框架结构为研究对象,分析对比阻尼等效前后结构正则坐标时程曲线,结果表明,阻尼等效前后正则坐标时程吻合度较高,由此研究了设置非线性黏滞阻尼器框架结构的地震作用.

The equivalent damping ratio and seismic action of the frame structure with nonlinear viscous dampers is studied.The vibration equation of a multi-degree-of-freedom energy dissipation frame structure is constructed.Based on the principle that the total amount of damping energy dissipation and the amplitude of regular coordinate of each order of vibration are invariant before and after the equivalent conversion of damping,the analytical formula for calculating the equivalent damping ratio of the first order mode of energy dissipating structure is established.On the basis,the formula for calculating the equivalent damping ratio of higher order modes is given by the Fourier transform method.Finally,a 10-storey reinforced concrete frame structure with nonlinear viscous dampers is taken as the research object,and the time history curves of the regular coordinate of the frame structure before and after the equivalent conversion of damping are analyzed.The results show that the time history curves of the first-order regular coordinate before and after the equivalent conversion of damping are in good agreement.From this,seismic action of the frame structure with nonlinear viscous dampers is investigated.