Experimental study on flexural performance of a novel prefabricated bent‐up reinforcement dowel connection for accelerated secondary lining construction

Abstract In the context of accelerated tunnel secondary lining construction requirements, although conventional circumferential reinforcement connections are technologically mature, the on‐site binding process for rebar splices entails substantial manual labor and high labor costs. To overcome the limitations of tedious on‐site work in the confined working space, this study proposes a novel connection method—the prefabricated bent‐rebar dowel (PBRD) connection—in secondary lining construction. Four‐point bending tests were carried out on five slab specimens with PBRD connection by varying the number of weld points and the diameter of dowel bars. In addition, one conventional reinforced concrete slab was also constructed and tested. Load‐deflection response, crack development, stiffness evolution, and strain distribution in the reinforcement were analyzed. Results demonstrate that the flexural performance of the specimens with PBRD connection is comparable to that of the conventional specimen. Both the number of weld points and the diameter of dowel bars were found to have a marginal influence on the flexural capacity and stiffness, confirming the robustness, and reliability of the proposed PBRD connection system. Furthermore, an analytical model for predicting the flexural capacity of the PBRD connection is developed, and the calculated moment capacity shows good agreement with experimental values, which could provide a reference for design and construction of secondary lining using the PBRD connection.