NONSTATIONARY RANDOM RESPONSE OF AN ELASTO-PLASTIC SDOF SYSTEM TO EVOLUTIONARY SPECTRUM-BASED GROUND MOTION USING THE CENTRAL DIFFERENCE METHOD

Abstract

This study proposes a time-domain method for evaluating the variance and covariance of the response of an elasto-plastic SDOF system subjected to nonstationary input ground motion modeled using an evolutionary spectrum. The Bouc-Wen model is employed to describe the restoring force, and the central difference method is applied to derive difference equations for the variance-covariance matrix, which are solved without equivalent linearization. The results are then utilized to estimate the maximum response distribution based on the level crossing statistics of the envelope process. The effectiveness of the proposed method is demonstrated through comparisons with Monte Carlo simulations.