Abstract
The purpose of this study is to investigate the commonness and difference between seismic responses of 3-dimensional structure-pile foundation-ground systems and those of 2-dimensional systems. In performing the 2-dimensional FEM analysis, the determination of thickness of the ground model is one of the most difficult problems. We obtained the optimum ratio of the thickness of ground to that of foundation structure which give the least difference between 3-D and 2-D analysis by performing parametric analysis by changing the number of piles and the height of structures. The results indicate that the responses of 3-D structure-pile foundation-ground systems can be estimated from the responses of 2-D systems by introducing correction coefficients. The coefficients were almost constant according to the number of rows of piles irrespective of the height of the structure.
