Flexural Performance Analysis of UHPC Wet Joint of Prefabricated Bridge Deck

The wet joint's mechanical performance determines the service performance of the prefabricated bridge deck. UHPC has an excellent application prospect in the 'joint area' of precast assembly bridge. This paper presents an experimental study to analyze the flexural behavior of the UHPC wet joint (with joint width of 15 cm) of the prefabricated bridge deck. Four specimens of prefabricated bridge deck were designed and manufactured, an integral concrete bridge deck (Z–T), used as the reference specimen, and the other three specimens were prefabricated bridge deck models with different joint section forms and steel bar connection modes. Based on the test of the flexural performance of the bridge deck with UHPC in situ cast joint, the influence of the cross-section form of funnel-shaped joint, wedge-shaped joint, U-shaped reinforcement, and arc-shaped reinforcement on the crack development, flexural capacity, and mechanical performance of the joint structure was studied, and compared with the integral concrete slab. The test results show that there was no crack in the UHPC joint, and the interface bond strength between the cast-in-place UHPC and the normal concrete of the prefabricated slab was high. The main crack was located in the normal concrete of the prefabricated slab beside the joint. The flexural capacity of the bridge deck with a width of 15 cm was the same as that of the whole concrete slab. Furthermore, it was found that the difference of ultimate bearing capacity between the joint slab and integral concrete slab was less than 2%, and the failure mode was the same. The wet joint structures proposed in this paper will not reduce the bearing capacity of the bridge deck.