Stiffness Analysis of Fiber-Reinforced Rectangular Seismic Isolators

Abstract

The reinforcing elements of multilayer elastomeric isolation bearings, which are normally steel plates, are replaced by a fiber reinforcement. The fiber-reinforced isolator is significantly lighter and could lead to a much less labor-intensive manufacturing process. In contrast to the steel reinforcement, which is assumed to be rigid, the fiber reinforcement is flexible in extension. This paper presents theoretical approaches for analyzing the compressive stiffness and bending stiffness of fiber-reinforced rectangular isolators. The influence of fiber flexibility on the stiffness of isolators is studied. In addition to theoretical stiffness solutions which are expressed in series form, simplified stiffness formulas based on the solutions of an infinitely long strip pad are also presented.