基础平动与转动结构随机地震响应分析的复模态法

The complex modal methods for analysis of random earthquake response of structures with horizontally translational and rotational base

本文对基础平动与转动结构随机地震响应问题进行了系统研究。首先建立了结构运动方程,然后针对体系运动方程为非经典阻尼的情况,用复模态法解耦获得了体系位移、速度和加速度随机地震响应的解析解,最后通过一个例子来说明考虑结构-地基相互作用的必要性。本文方法可推广到非平稳地震响应分析。

The random earthquake responses of structures with horizontally translational and rotational bases were studied systematically. The dynamic equations were established firstly. Then, according to the situation of the non-classical damping, the complex mode theory was used to decouple the equations, and the exact solutions of displacement, velocity and acceleration responses were got. The example shows that the deviations of displacement, velocity and acceleration of structure are increased 36.29%, 113.63%, 8.22%,respectively than the immovable base when considering translational and rotational base. So considering the effect of horizontally translational and rotational base for the structure-soil interaction is necessary. The method presented can be used to non-stationary random earthquake response analysis.