Comparison of performance of shape memory alloy reinforced bridge piers with conventional bridge piers using incremental dynamic analysis

Abstract

Bridge piers built in active seismic regions can sustain large residual displacements following a strong earthquake. In many recent major earthquakes residual displacement enforced demolition of bridge piers due to the serviceability and/or safety concerns. Consequently, in order to reduce residual displacement after major earthquakes many innovative methods were explored in the last decade. One of such innovative method is to replace the conventional longitudinal steel reinforcement in the plastic hinge regions of bridge piers with super-elastic Shape Memory Alloy (SMA). This study numerically investigates efficacy of SMA reinforced concrete bridge piers on mitigating the residual displacement after major seismic events. In this study, firstly numerical model and the computational platform used for the analysis are validated using data from shake table experiment of scaled SMA reinforced pier. Then numerical study on three prototype bridge bents with single and multiple piers are conducted to compare the effectiveness of using the SMA bars in plastic hinge regions to reduce the residual displacement of the bridge piers. The seismic performance of the three bridge bents with steel and SMA reinforced piers are evaluated using incremental dynamic analysis. The numerical results demonstrate the effectiveness of using SMA reinforcement on reducing the permanent displacement of bridge piers after severe earthquake shakings