Abstract: To investigate the shear behavior and influencing factors of assembled reinforced concrete (RC) bridge piers with mortise and tenon-cast-in-situ UHPC hybrid connection, quasi-static tests were conducted. Based on the experimental results, a refined finite element model was established to systematically analyze the effects of key parameters, including axial compression ratio, longitudinal reinforcement ratio, stirrup ratio, and UHPC thickness, on the shear capacity of the specimens. Meanwhile, existing calculation methods for the shear strength of precast assembled bridge piers were reviewed. Using the finite element results as the basis, the applicability and accuracy of the shear strength formulas in relevant domestic and international design codes were evaluated, and a modified shear strength calculation formula applicable to precast assembled bridge piers with hybrid connection joints was further proposed. The results indicated that the mortise-tenon and cast-in-situ UHPC hybrid-connected assembled RC bridge piers exhibit favorable shear performance, the modified calculation method proposed demonstrates higher accuracy and better applicability.

Key words: bridge engineering, assembled bridge piers, mortise-tenon connection, ultra-high performance concrete, shear resistance