ABSTRACT
To compare the flexural behavior of wet joint of UHPC slab with different rebar connection and joint structure, the research was conducted by model test, based on a double-T UHPC Girder Bridge in highway. A series of bridge deck slab specimens were designed and prepared to perform pure bending tests so as to study the cracking development, failure mode ,cracking load, failure load, etc. The results showed that the new-old UHPC interface, as a weak site of entire specimen, cracked firstly. The UHPC bottom mould saved site construction time, greatly increased the crack and failure load more than 30% compared with the monolithic slab. For U-shaped rebar connection specimens, the contribution of increasing rebar ratio to load-bearing performance was significantly greater than whether the reinforcement was connected or not. The ultra-thin wet joints of 23cm wide UHPC-U shaped rebar can meet the stress requirements of the structure in the serviceability limit state and the bearing capacity limit state.
