基于无限元和波场分离法的地震响应数值分析

Numerical analysis of seismic response based on infinite element and wave field separation method

摘要:

用无限元模拟远场地基，有限元模拟近场区域，并在有限元和无限元接触处施加等效荷载以输入地震作用，从而实现对半无限地基的地震响应进行求解。结果表明，基于无限元以及等效荷载输入的方法，能够有效仿真波动在半无限地基中的传播过程。此外，还探讨了重力对自由场地震响应的影响，并以一个核电站地基的地震响应为例，分析了结构地基相互作用对地震响应的影响。

Abstract:

This paper uses the infinite element to model the far field and the finite element to model the near field of foundation, and the equivalent load is artifically applied to the interface between the finite element and the infinite element to replace the seismic action. The seismic response of semi-infinite foundation are then simulated. Numerical results show that the proposed methodology based on the infinite element and the equivalent load method is feasible and can effectively simulate the process of wave propagation in semi-infinite foundation. Besides, the effect of gravity on the seismic response of free field is analyzed. Finally, the effect of soil-structure interaction on seismic response is also investigated via an engineering example of nuclear plant foundation.