Evaluation of shear behavior of PCSC shear connection for the construction of composite bridges with prefabricated decks

Abstract

Conventional stud connectors are commonly used in composite bridges with prefabricated concrete decks. However, the reserved holes for grouped studs cause difficulty in the prefabrication of the concrete deck, due to tedious pouring operation during construction, which might weaken the integrity of the deck. Therefore, a precast concrete deck–steel beam–connection concrete (PCSC) connector is proposed in this study to accelerate the prefabrication and construction of a steel–concrete composite bridge. A series of static push-out tests were performed to verify the mechanical properties of the PCSC connectors. The test results indicated that the shear capacity of the PCSC connectors of the standard specimen was 12.27% higher than that of conventional clustered shear stud connectors with a diameter of 16 mm. Additionally the ultimate slip was 47.42% higher than that of the conventional stud connectors. The PCSC connector had a high capacity and ductility. The PCSC connectors had a high tolerance for precast concrete-connection concrete (PC–C) interfacial defects. Rough PC–C interfaces did slip during loading until the interface disengaging rate (i.e., the ratio of defect area to the total interface area) was less than 70%. The failure of the connector was controlled by the stud even if the slip occurred at the PC–C interface under the premise of sufficient shear connection reinforcement. A finite-element analysis was conducted to evaluate the load transfer mechanism of the PCSC connector. Finally, a comparative analysis demonstrated that the bearing capacity of the PCSC connector was accurately predicted by AASHTO LFRD.