Hybrid Discrete Method for Seismic Response Analysis of Soil-Structure System with Topographical Site Consideration

考虑地形场地的土-结构系统地震响应分析的混合离散方法

基本信息

批准号：
63550340
负责人：
TAKEMIYA Hirokazu
金额：
$ 1.41万
依托单位：
Okayama University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1989
项目状态：
已结题

项目摘要

This paper concerns the surface soil response during earthquake motion with particular interest on the topographial condition. In the so-called near field which includes structures, certain distribution exists in soil properties as well as some irregularities in boundary condition. The far field which extends outside the near field is often assumed as a uniform or heterogeneous. The finite element method is taken for the former near field while the boundary element method is used for the latter far field. For the seismic wave incidence, we specify the wave type such as P-, SH-, or SV-wave of plane wave. For the numerical case studies, half-circle, half-ellipse, and trapezoidal alluvium are used with different soil properties. Also, parametric studies are made with changing the wave length of the incident wave and the size of the alluvium. The topographical site effect is clarified in comparison with the results from heterogeneous models.For the soil-structure interaction analysis, interest is placed on deriving the soil impedance function and the effective input motion for certain type foundation. The soil is assumed as axisymmetric layered. The Fourier series expansion is used for describing the response. The parametric studies are performed to discuss the foundation behavior for different incident wave type, angle of its incidence.The effort is made to evaluate the relevant Green functions for the above purposes. The direct stiffness method is applied for evaluating the wave number domain and the numerical inversion is taken to get the inverse Fourier transform for the space domain solution.

本文关注地震运动期间地表土壤的响应，特别关注地形条件。在包括结构在内的所谓近场中，土壤性质存在一定的分布，边界条件也存在一定的不规则性。延伸到近场之外的远场通常被假设为均匀场或异质场。前者近场采用有限元法，后者远场采用边界元法。对于地震波入射，我们指定波型，例如平面波的 P 波、SH 波或 SV 波。在数值案例研究中，使用了具有不同土壤特性的半圆形、半椭圆形和梯形冲积层。此外，还通过改变入射波的波长和冲积层的大小进行了参数研究。通过与异质模型的结果比较，阐明了地形场地效应。对于土-结构相互作用分析，重点在于推导特定类型地基的土阻抗函数和有效输入运动。假设土壤为轴对称层状。傅立叶级数展开用于描述响应。进行参数研究以讨论不同入射波类型、入射角的基础行为。出于上述目的，我们努力评估相关的格林函数。采用直接刚度法评估波数域，并采用数值反演得到空间域解的傅里叶逆变换。