FINITE-ELEMENT ANALYSIS OF LAMINATED RUBBER BEARING USED IN BASE-ISOLATION SYSTEM

A realistic mechanical model was proposed for the laminated rubber bearing, one of the most important structural members in the base-isolation system. The model was analyzed by means of the finite-element method (FEM), up to the range of large deformation under high compressive load. The physical characteristics of the rubber material was modeled using a strain-energy-density function based on the biaxial elongation tests. The load-deformation relationship calculated by FEM using such strain-energy-density function agreed well with experimental results. Based on the simulated stress and strain distributions in the laminated rubber bearing, a mechanism of supporting the vertical load during horizontal deformation was proposed.