Calibration and Validation of Analytical Models for Predicting the Seismic and Axial-Load Response of Circular Bridge Columns

Abstract

The objective evaluation of the capacity of a bridge to carry self-weight and traffic loads after an earthquake is essential for a safe and timely reopening of the bridge; this performance goal gains in importance with the recognition of the economic losses caused by the reduced traffic capacity of the transportation systems of a region affected by an earthquake. An analytical model of a bridge column was developed, calibrated, and validated to facilitate the quantitative evaluation of the remaining traffic-load capacity of a typical California highway overpass bridge after an earthquake. The bridge-column model was developed using a fiber cross section, force-based beam-column element with distributed plasticity. The model was calibrated using the data from a series of bidirectional quasi-static tests and validated using the data from hybrid simulations of the bridge earthquake response. It was found that the postpeak degrading slope of the confined-concrete core has a significant influence on the accuracy of the axial-load capacity of damaged columns.