黏滞阻尼器考虑激励频率影响的附加阻尼比简化计算

目前减震结构的附加阻尼比计算都需要先计算出结构的动力反应,并进行复杂的迭代过程,且在计算中一般都仅考虑激励频率等于结构基频的情况.基于非线性黏滞阻尼器,提出了一种不需计算结构动力反应,只根据结构特性、激励频率和阻尼器参数直接求解结构附加阻尼比的计算方法.分析了目前常用的几种附加阻尼比的计算方法,推导出了减震体系在简谐激...

Simplified calculation of supplemental damping ratio of viscous damper considering excitation frequency

At present,it is necessary for the calculation of the supplemental damping ratio of the aseismic structure to calculate the dynamic response of the structure and perform the iterative process.In addition,generally only the case where the excitation frequency is equal to the fundamental frequency of the structure is considered.Based on the nonlinear viscous damper,a calculation method that without calculating the structural dynamic response directly obtains the structural supplemental damping ratio based on structural characteristics,excitation frequency and damper parameters is proposed.Firstly,several frequently used methods of calculating supplemental damping ratio are analyzed.Then,the calculation formula of the supplemental damping ratio for the excitation frequency equals to the fundamental frequency of the structure,and without calculating the structural dynamic response and the iterative process is deduced.By studying on the influence of the excitation frequency on the calculation of the supplemental damping ratio for different damping indexes,a simplified calculation formula for supplemental damping ratio in the case of non-resonance is proposed.On this basis,taking response spectrum average period as the excitation frequency of the ground motion,a simplified calculation method of the supplemental damping ratio considering the excitation frequency and no need to calculate the structural dynamic response is given.Finally,the accuracy of the proposed method is verified by comparing the results of the example with the results of nonlinear time history analyses.