Development and Study of a Building Model on Lead Rubber Bearings

Abstract

The building structures on the lead rubber bearings (seismic bearings) require nonlinear dynamic analysis in the time domain. However, in performing such analyses, it is quite difficult to assess the influence of the seismic bearing characteristics on structural dynamic response and quality of seismic isolation in a whole. To solve this problem, it is proposed to study simple nonlinear models with a small number of degrees of freedom. A planar shear model of a three-storey building on lead rubber bearings implemented in the Matlab software is considered. Seismic excitation on the building is given by artificial accelerograms. When subjected to cyclic loads, the building seismic bearings show a significantly nonlinear behavior described by a bilinear deformation diagram with hysteresis. The nonlinear equations of motion for a seismically isolated three-storey building are derived, and procedures for seismic load modeling and numerical integration of the equations of motion are described. The results of numerical simulation for various hysteresis parameters are obtained and analyzed, and conclusions about the seismic protection effectiveness are drawn. The obtained study results may be of interest for design engineers from the viewpoint of elaborating their own simple models for testing seismic isolated building structures and studying the influence of various hysteresis parameters on the seismic isolation quality.