A seismic analysis of a soil-structure interaction system incorporating infinite elements is presented in this thesis. The main purpose of this study is to adopt and verify a new effective sesmic wave input procedure for the earthquake response analysis.
The procedure of the seismic analysis consists of two steps : the free field analysis and the earthquake response analysis. In the free field analysis, the frequency-dependent dynamic stiffness matrix method is used. Any incident wave angle can be considered, and both P-wave and S-wave components can be taken into account. From the free field analysis results, the equivalent earthquake forces along the interface between the near and the far fields are obtained. Then, the earthquake response analysis is carried out using the equivalent earthquake forces. A three-dimensional axisymmetric finite element computer program KIESSI for soil-structure interaction analysis incorporating infinite elements for the far field soil region, has been updated for this purpose. For the efficient analysis, the wave input procedure recently developed is utilized.
The example analysis is carried out for a test structure used in the earthquake response measurements. From the comparison with the results by other programs and the experimental data, it has been found that the present method gives fairly reasonable results for the earthquake response of soil-structure system.