Analytical prediction of mechanical properties in horizontal direction of lead-rubber bearings

Abstract

Application of seismic isolation devices is an efficient way for designing seismically resistant structures. For that purpose, various types of seismic isolation devices are developed. The main differences between them are in the materials used for their production and in the way they provide horizontal flexibility. Dynamic analysis of a base isolated structure requires an adequate mathematical model of the seismic isolation devices which can describe their mechanical properties in horizontal and vertical directions. The paper is considering analytical models used for the prediction of mechanical properties in the horizontal direction of lead-rubber bearings, which are proposed in the contemporary literature. Results obtained using these analytical formulas are compared with the results obtained by the finite element analysis model developed in this paper, as well as with available test results provided by the manufacturer. Improvements of the existing analytical models are suggested in order to enable a better prediction of mechanical characteristics in the horizontal direction of lead-rubber bearings.