Experimental Research on Shear Performance of Joint Interface in Prefabricated Viaducts

The segmented construction with wet joints is one of the most effective methods to solve the transportation and installation difficulties of large prefabricated concrete viaduct components. To study the shear performance of the joint surface at the wet joint, four groups of 12 specimens were designed for double shear tests, taking into account the effects of reinforcement, concrete strength grade, joint surface roughing process, and other factors. The mechanical bite force coefficient c of the joint interface roughing process in the extended shear friction theory formula was fitted by using the least squares method. The research results showed that the joint surface roughing process had a significant influence on the shear bearing capacity of the specimens. The bearing capacity of the specimens with exposed aggregate, plastering strip, and chiseling surface roughing treatment were approximately 92.7% to 94.1%, 82.7% to 86.7%, and 66.7% to 71.1% of that of the monolithic specimens, respectively. The connecting rebars of joint surface could significantly improve the ductility, shear bearing capacity, and crack resistance of the specimens, and the increase in bearing capacity was about 47.3% to 65.0%. When the specimens reached the ultimate state, the strain distribution of the connecting rebars of joint surface was uneven, and the average strain of all the rebars was about 50% of the yield strain. The calculated values of the shear bearing capacity of various country codes were much lower than the test values, indicating a high safety margin. The fitted parameters could provide a reference for engineering applications.