AN APPROXlMATED CURVE HYSTERETIC SIMULATION MODEL FOR SEISMIC RESPONSE OF STEEL BRIDGE PIERS

Abstract

In this paper，an approximated curve hysteretic model is proposed to predict the seismic response of steel piers under strong ground motion. Instead of multiple stright lines，a series of curves are adopted to descript the complicated force-displacement hysteretic relationship of steel piers. P-δ effect，hardening effect in unloading-reloading hysteretic loops，deterioration characters of steel columns are considered in this model by introducing hysteretic rules and identifying free parameters. To verify the accuracy of the proposed model，six static cyclic tests and eleven hybrid tests using three types of steel pier specimens are conducted under the six strong ground motion records. By comparing the results due to the hybrid tests and the simulation，the average difference between these two is clarified as 5% in maximum response displacement，22% in residual displacement and 3% in energy absorption.