基于拟力法的基础隔震结构抗震性能和能量分析

Seismic performance and energy analysis of isolation structures based on the force analogy method

基于拟力法基本理论,建立了隔震结构杆系计算模型,同时考虑隔震支座的剪切变形和弯曲变形的影响,推导了基础隔震结构的运动方程和能量方程,编制程序对隔震结构进行地震下的动力非线性分析和能量分析。通过与SAP2000计算结果的对比,验证了本文方法的有效性和程序的正确性。数值算例结果表明,本文提出的方法与变刚度的时间积分法相比计算效率明显提高;本文方法可以考虑上部结构的非线性,可以得到隔震支座及上部结构各构件的塑性耗能;通过对比基础隔震结构和抗震结构在地震作用下的位移、加速度及耗能情况,证明了隔震结构的隔震效果。本文拓展了拟力法的应用范围,为隔震结构的动力非线性分析及能量分析提供了一种新思路。

Based on the principle of force analogy method, a pole-system model for a base-isolated structure was es- tablished. Considering bending and shear effects of rubber isolation bearings at the same time, the motion equations and energy equations of a base-isolated structure were derived and proposed. The dynamic nonlinear analysis and energy analysis were done for the base-isolated structure by programming. Compared with the results obtained by SAP2000, the validity of the presented method and the accuracy of the program were verified. Numerical simulation results indicated that the proposed method shows higher computational efficiency compared with the variable stiff- ness time integration method; The proposed method could consider the nonlinear of upper structure and calculate the plastic energy dissipation of isolation bearings and the upper structure＇ s components. Through compared the displacement, acceleration responses and energy dissipation of a base-isolated structure with an aseismic structure under the action of earthquakes, the isolation effect of the isolated structure was verified. The application of force a- nalogy method was expanded and a new method for the dynamic and energy analysis of base-isolated structures was provided.