The purpose of this study is in order to grasp the behavior of rubber bearings in strong motion by using the three-dimensional analysis model. It was confirmed that the axial force of rubber bearings received not only the earthquake ground motion but also the influence of the building shape. Because effective area of rubber bearings supporting isolated buildings is decreased by horizontal deformation, the axial force acting on effective area becomes large. The axial force evaluation method which is used in this paper is effective in most cases, but it is necessary to note it to become undervaluation in part.
