Analytical Seismic Fragility Curves for Reinforced Concrete Wall pier using Shape Memory Alloys considering maximum drift

Fragility curves express the seismic vulnerability of bridge piers for different damage states at various earthquake intensities. A fragility curve typically gives a physical understanding of repair costs and functionally levels of a bridge pier. Shape memory alloys (SMAs) provide a promising alternative material in reducing the failure probability of a bridge pier. This study develops a family of seismic fragility curves for reinforced concrete (RC) wall piers reinforced with three different types of SMA rebar in plastic hinge regions. An incremental dynamic analysis (IDA) using a total of 20 earthquake ground motions was performed on a SMA-RC wall pier to evaluate its seismic performance. The maximum drift recorded for each ground motion was taken as the seismic performance demand parameter of interest in this study. The probabilistic seismic demand model (PSDM) was used to generate fragility curves for each RC-SMA wall pier. The results show that the different mechanical properties and type of SMAs affect the performance of RC-SMA wall pier.