DESIGN FORMULAS FOR ROTATIONAL DEFORMATION OF LAMINATED RUBBER BEARINGS BASED ON FINITE ELEMENT ANALYSES

Abstract

  This paper presents design formulas for rotational deformation of natural rubber bearings on the basis of finite element analyses of the bearings. At first, a natural rubber often used in the bearings is modeled by hyperelastic damage model, based on several material tests. In addition, a material property, which is equivalent to elastic limit of tensile deformation of the bearings, is identified by simulating one of the tests. Then, critical angles of rotational deformation of the bearings are computed through simulations, where shapes-factor, vertical load and initial horizontal deformation are changed. From results of the simulation, simple formulas approximating the critical angles are proposed, and they are found to exhibit larger values in comparison with present design code. Finally, validity of the proposed formula is verified by fatigue test on rotational deformation of a bearing.