The Three Dimensional Finite Element Analysis of a Rubber Bearing Using the Selective Integration Method.

Abstract

For finite element analysis of hyperelasticity such as rubber material, the mixed method and the selective integration method have been used widely. These methods can optimize volumetric constraint and degree of freedom of stiffness matrix. In the mixed method, the mean stress and the deviatoric strain are separeted and formulated. In the selective integration method, the reduced and full integration rule is applied to the terms including the mean stress and the other. Laminated rubber bearings consisting of thin rubber films and steel plates are used as seismic isolation device to reduce horizontal earthquake response of structure. Recently, laminated rubber bearings using thick rubber films is considered to use as seismic isolation device to reduce both horizontal and vertical response. In this paper, formulation of a selective integration method in rate form is made and results of three dimensional finite element analysis of rubber bearings are shown along with the comparison with experimental results.