Development of fragility curves for retrofitted

This study focuses on developing fragility-based seismic vulnerability assessment techniques for seismically retrofitted multi-column bridge bent. Fragility curves are developed using Probabilistic Seismic Demand Model (PSDM) to assess the relative performance of different retrofit methods under near fault ground motions. Two different retrofit techniques namely CFRP jacketing and ECC jacketing are used in this study. The distinctive and catastrophic features of near fault ground motions place serious demand on structures located in the near field region of an earthquake and require special attention. In order to investigate the near fault ground motions effects, a total of 20 near fault ground motions are utilized to evaluate the likelihood of exceeding the seismic capacity of the retrofitted bridge bent. Results obtained from this study indicate that the properties of retrofitting materials have a significant effect on the damage probability of the retrofitted bridge bents. The findings can serve as a guide to express the impact of retrofit on the bridge bent vulnerability.