Structural performance at the joint of precast pile-supported pier structure

Recently, precast construction methods have been increasingly applied to pile-supported pier structures in coastal areas, offering simplified construction processes, shorter construction periods, and minimized environmental pollution. The use of precast members in offshore construction allows for prefabricated assembly, reducing the need for temporary installations and minimizing field casting work. However, pile-supported pier structures in coastal regions are subject to various marine loads, such as wave, berthing, wind forces and live load, along with uplifting forces due to sea-level rise, making it essential to verify the joints—typically the most vulnerable part of precast structures. This study conducts numerical analyses and experimental tests to evaluate the behavior of joints in newly developed precast structures and assess their structural safety. Results indicate that the failure mode of the structure initiates and progresses at the joint where the precast members connect to field-cast sections. Additionally, it was confirmed that failure originates at the weakest point in areas where precast girders, precast pile caps, and piles are interconnected. Nonetheless, the proposed structure demonstrated structural performance that significantly exceeded the design load.