黏滞阻尼器消能减震结构在多遇地震下附加阻尼比计算方法对比研究

Comparative study of additional damping ratio calculation method for energy dissipation structures with viscous dampers under frequent earthquake

确定消能减震结构在多遇地震作用下阻尼器的等效附加阻尼比是消能减震结构设计的关键。较易于应用在工程实践的三种等效附加阻尼比计算方法分别为:规范反应谱法、规范时程法和时程能量比法。本文参考层模型概念给出了规范时程方法中阻尼器耗能和结构应变能的一种计算方法;讨论了能量等效的理论依据和基本假定;评述了三种方法的优缺点。为避免时程分析中地震动的离散性,本文时程分析采用了人工合成地震动。基于自主研发软件,使用上述三种方法计算了某实际消能减震结构的等效附加阻尼比,讨论了三种方法的差异。

The key step of the energy dissipation structure design is to calculate the equivalent additional damping ratio of the damper under frequent earthguake.There are three equivalent additional damping ratio calculation methods:code response spectrum method,code time-history method and time-history energy ratio method,which are easily usded in engineering practice.Base on the concept of structural layer model,a method of calculating the energy dissipation of the damper and structural strain energy in the code time-history method is given in this paper.The theoretical basis and basic assumption of the time history energy equivalent method are discussed.The advantages and disadvantages of the three methods are reviewed.In order to avoid the discreteness of the ground motions,the artifical ground motions are used in time history method.The equivalent additional damping ratios of an energy dissipation structure are calculated by the three methods mentioned above,and the differences are analyzed.