Performance-Based Damage States for Seismic Retrofitting of Reinforced Concrete Bridge Bent

Performance-based seismic design approach is implemented to achieve a desired structural performance under a specific seismic hazard level. It requires defining a set of targeted performance levels and their corresponding limits. As current codes and guidelines do not prescribe such limits for different performance levels of bridges with seismic deficiencies such as inadequate ductility and low shear strength, this study aims to develop them. In this paper, quantitative damage states expressed in terms of maximum drifts at various performance levels are developed using incremental dynamic analyses for retrofitted bents. Four retrofit options, e.g., steel, carbon fiber-reinforced polymer (CFRP), concrete, and engineered cementitious composite (ECC) jackets are considered in this study. Concrete and longitudinal reinforcement of all bents cracked and yielded at limiting drifts of 0.06% and 0.38%, respectively. Besides, the ECC jacketed bent experienced core crushing of concrete at the highest limiting drift of 4.16%. The developed damage states can be used for performance-based seismic retrofit design of seismically deficient bridge bents.