Abstract

This paper evaluates the effects of Soil-Structure Interaction (SSI) on the seismic response of multi-story concrete frames subjected to earthquake ground motions. To calculate the structural response, an iterative Wave-Propagation (WP) based method has been used. The exact solution of SSI problems, in addition to high computational costs, due to general complexity of finite element analysis, require an advanced computer system. According to the method proposed herein, buildings were modelled as an extension of the layered soil media by considering each story as a layer in the WP path. The motion in each layer could be determined from the motion in any other layer. This permitted to use an operation called deconvolution, which could be considered to investigate the effect of substructure soil layers on the structural response. One of the capabilities of WP method is to facilitate the computation of bedrock motion from a known free surface motion and consequently determination of correct foundation input motion. While most of the current methods assume constant values for basic parameters such as; stiffness and damping, in the present method in order to investigate the nonlinear behaviour, stiffness and damping are proportional to the displacement level of soil layers or structural floors. The computational speed and accuracy of the proposed method are also verified by a benchmark frame analysis. Also, based on the Park-Ang Damage Index, this paper evaluated the measures of damage (the relationship between earthquake characteristics (PGA) and damage level) which govern structural degradation and/or collapse obtained from different well-known destructive earthquakes.

摘要

本文评估了土-结构相互作用（SSI）对经受地震地震动的多层混凝土框架地震响应的影响。为了计算结构响应，已使用基于迭代波传播（WP）的方法。由于有限元分析的一般复杂性，除了高昂的计算成本外，SSI问题的精确解决方案还需要先进的计算机系统。根据本文提出的方法，通过将每个故事视为WP路径中的一层，将建筑物建模为分层土壤介质的扩展。可以根据任何其他层中的运动来确定每一层中的运动。这允许使用一种称为反褶积的操作，可以考虑用来研究子结构土层对结构响应的影响。WP方法的功能之一是便于根据已知的自由表面运动来计算基岩运动，从而确定正确的地基输入运动。虽然大多数当前方法都为基本参数假定常量值，例如；刚度和阻尼，在本方法中，为了研究非线性行为，刚度和阻尼与土层或结构层的位移水平成正比。还通过基准框架分析验证了该方法的计算速度和准确性。另外，基于帕克-安格损伤指数，本文评估了控制由不同著名破坏性地震获得的结构退化和/或倒塌的破坏程度（地震特征（PGA）与破坏程度之间的关系）。