IMPROVEMENT OF STRESS-STRAIN RELATION UNDER MULTIAXIAL LOADING OF RUBBER FOR BEARINGS

Abstract

 Since rubber bearings play an important role in the seismic design of bridges, it is necessary to accurately evaluate their deformation and fracture characteristics. Rubber material of a bearing is subjected to a huge shear deformation as much as several hundred percent before it fails, and has inherent properties of rubber materials such as hyperelasticity, plasticity, and viscosity. It is necessary to consider the complex stress-strain relationship. For these reasons, many studies have been conducted on accurate numerical simulation of rubber bearing behavior. In this study, we focus on the Mullins effect peculiar to filled rubber and the plastic behavior of rubber materials that have been relatively untouched. The necessary and reasonable improvements were made to these formulations, and the experimental results were shown to be better reproduced.