Seismic Performance of Flared Precast Segmental Self-Centering Bridge Columns: A Numerical Investigation

This study investigates the seismic performance of a novel flared precast segmental bridge column system through detailed finite element modeling. The proposed design incorporates flared lower segments to improve strength, energy dissipation (ED), and post-earthquake reparability, while maintaining the advantages of accelerated bridge construction. A parametric study was conducted by varying flare widths (500–600 mm) and flare height ratios (16–67%) to evaluate their effects on structural behavior. Key performance indicators included joint opening distribution, damage patterns, ED capacity, hysteretic response, residual drift, and the stress–strain demands on ED bars. Results indicate that the flared geometry significantly enhances lateral strength and ED capacity while maintaining the self-centering capability of the system. Notably, properly proportioned flare geometries achieved up to 65% greater lateral strength, 36% higher ED, and up to 37% reduction in residual drift compared to conventional straight columns. Additionally, flare height ratios between 33% and 50% provided optimal performance by promoting distributed inelastic deformation, reducing damage concentration at the base, and decreasing ED steel bar strain by up to 64%. In contrast, flare heights below 33% or above 50% led to concentrated damage and stiffness degradation. These findings offer practical design guidelines for optimizing flare geometry in precast segmental bridge columns to achieve high seismic resilience and improved post-earthquake functionality.