Multi-factor analysis and optimization on seismic behavior of precast pier-footing socket connection considering different connection parameters

Accelerated bridge construction technology, with its various connection methods, has experienced extensive global usage. Common methods include post-tensioned, cast-in-place joint, sleeve, and socket connections. Each method has its advantages and limitations, such as the energy dissipation issue in post-tensioned connections and the on-site challenges of cast-in-place joints. Precast pier-footing socket connections have emerged as a promising solution due to their rapid construction and durability. However, previous research has predominantly focused on the minimum embedded length, overlooking critical factors such as grouting material strength, shear key configuration, and axial compression ratio during service. Furthermore, existing studies often isolated individual factors, neglecting their interconnected effects. This study addressed these gaps by testing two specimens and analyzing thirty-eight models through experimental and numerical methods. The results indicated that an embedment depth of at least 1.0 times the diameter (bc) of the precast pier was recommended. Furthermore, to ensure optimal seismic performance, it was essential to enhance the stiffness of the footing sidewalls beyond this depth. Additionally, while shear keys improve bending resistance, their effectiveness decreases with greater embedment depth (>1.5 times the diameter). This study highlights the importance of considering the interplay of multiple factors to ensure project safety and cost-effectiveness.