Seismic performance of resilient self-centring bridge piers equipped with SMA bars

Abstract

This study examines the seismic behaviour of precast post-tensioned segmental (PPS) bridge piers that are equipped with shape memory alloy (SMA) bars. PPS piers are designed to minimise overall and localised damage to bridges by incorporating natural hinges and rocking mechanisms. The introduction of super-elastic SMA bars has the potential to enhance the use of PPS piers in highly seismic regions. A parametric study is conducted to identify piers with the highest energy dissipation capacity, which are then subjected to dynamic analysis. The aim is to assess the energy dissipation capability of these systems by subjecting the selected piers, both with and without SMA bars, to far-field ground motions using a finite-element framework. The seismic performance of the piers is evaluated using incremental dynamic analysis (IDA) curves, which are obtained from analysing the piers under 44 far-fault ground motions. The IDA results indicate a significant reduction in the drift responses of the piers when SMA bars are utilised.