中文摘要：

本文采用黏弹性边界方法和地震动输入等效结点力方法,并结合通用有限元软件ANSYS,建立了三维凹陷地形地震响应分析问题的模型。通过与文献比较,对层状场地中三维凹陷地形整体模型进行了精度验证,并以天津市深厚覆盖层场地中某三维凹陷地形为例进行了地震响应分析,研究表明,三维凹陷地形对地震动具有显著影响,地表地震加速度反应谱与自由场具有明显差别。本文模型为三维复杂局部场地地震效应的分析奠定了基础。

英文摘要：

This paper studies the model for seismic response analysis of 3D canyon based on the viscous-spring boundary and equivalent node force of earthquake excitation, combined with general finite element analysis software ANSYS. The model for 3 D canyon in layered half-space is validated through comparisons with the results in literature. Seismic response of a 3D canyon in Tianjin City with thick soil layers is implemented, and it is shown that 3D canyon has significant effect on the seismic ground motions, and their response spectra have evident difference with those of the free-field response. This model provides the foundation for seismic effect analysis of complex local sites.