Effect of a novel joint connection of UHPC wet joint and tapered sleeve locking-type couplers on the lateral cyclic response of precast segmental railway bridge columns

Due to the lack of reliable connections, precast segmental technology is rarely used to construct the railway bridge piers that required high lateral stiffness and strength. To address this problem, a novel connection using tapered sleeve locking-type couplers and ultra-high performance concrete (UHPC) wet joints is proposed to connect the segments of precast railway bridge columns. To explore the cyclic behavior of the segmental columns with this novel connection, three column specimens with a scale ratio of 1:3 were fabricated and tested. Specimen CIP was a monolithic column. Specimens PC-N and PC-UH were segmental columns with normal concrete and UHPC wet joints, respectively. The longitudinal reinforcements at the joints were connected by tapered sleeve locking-type couplers. Based on the quasi-static test results, the damage evolution processes of UHPC/NC wet joints, as well as the strength, ductility, residual displacement, stiffness degradation and energy dissipation of the specimens, were analyzed and discussed. The results showed that the precast specimens with the proposed connection exhibited plastic hinge shift formation and had higher strength and equivalent stiffness to that of the specimen CIP. Finite element modeling (FEM) was developed and calibrated based on the experimental results. The results obtained from the experimental works and FEM showed good agreement, demonstrating the applicability of the developed FEM.