Method for Evaluating Ground Stability Considering Lateral Resisting Effects Based on Pseudo Three-Dimensional Model

摘要

The stability of soil-structure systems is usually evaluated using a two-dimensional analysis. However, using a three-dimensional analysis may be one of the best methods to minimize unnecessary seismic safety margins which are potentially included in a two-dimensional analysis. This three-dimensional analysis however requires a substantial amount of man and machine power, which makes this method inefficient. Therefore a pseudo three-dimensional method is proposed for evaluation of the stability of the ground.The model of this pseudo three-dimensional method consists of multiple two-dimensional cross sections. By utilizing the results of static and dynamic responses from these multiple models, it is possible to create stress conditions along three-dimensional failure surfaces that are similar to those results from a three-dimensional response analysis. This method was applied to a hypothetical example with weak layer zones and a site with fault zones that actually exists. The first example consisted of three individual cross sections and the second example consisted of more than 10 cross sections. The factors of safety are compared to those from a three-dimensional analysis. The results compared were consistent each other. Therefore it is concluded that the proposed method produced reasonable and accurate results for the design purpose.