Reliability Analysis of a Bridge Pier Supported on a Rocking Shallow Foundation under Earthquake Loading

Abstract

Guidelines on the response analysis of rocking shallow foundations considering material uncertainties under earthquake loading are not available in any great detail. In this study, a reliability analysis of a bridge pier with a rocking shallow foundation (RSF) was performed, using the Monte Carlo simulation technique, applied on the performance functions of the bridge pier, approximated using the response surface method. The soil–structure interaction was modeled using a beam on the nonlinear Winkler foundation approach. Two ground motions, corresponding to moderate and strong seismic intensities, were used in the study. Four model configurations of the bridge pier–RSF system were considered, and the probabilities of failure were evaluated, corresponding to three performance levels. It was concluded that the probabilities of failure changed drastically with the performance level of the bridge pier. The results showed that the bridge pier–RSF system suffered minimal damage during the moderate earthquake and was effective in enhancing seismic performance during the strong earthquake.