Numerical study on shear performance of stud-PBL shear connector in corrugated steel plate-UHPC layer composite deck
A combined shear connector has been proposed for the innovative composite bridge deck consisting of corrugated steel plate and UHPC(Ultra-high Performance Concrete)layer.Short studs are suggested to be fixed at the wave peak of the corrugated steel plate,while PBLs(Perfobond Leiste)are recommended to be fixed at the wave trough.Numerical models were established to investigate the shear behavior of the corrugated steel plate-UHPC interface combined shear connector.The models were verified using existing experimental results.The shear performances of the combined shear connector were analyzed,taking into account design parameters such as stud diameter,PBL hole size,stud tensile strength,and UHPC strength.This allowed for the revelation of the failure mechanism and cooperative working mechanism between the stud and PBL.The formula for calculating the shear capacity and design method of the combined shear connector was proposed.The analysis focused on the distribution of shear force in the combined shear connector during the push-out test.The results indicate that the shear force of the combined shear connector was jointly borne by the studs and PBLs.The increase in stud diameter,PBL hole size,and UHPC strength improves the shear capacity of the combined shear connector.The PBL,which does not have steel bar damages,fails earlier than the stud despite having similar shear capacities.When the ratio of shear capacities between PBL and stud is about 1.5,the PBL and stud fail around the same time,and the best combination effect is achieved.The formula for the combined shear connector's ultimate shear capacity is highly precise,and the calculated results align well with both FEM and experimental results.The composite deck joined with combined shear connector exhibits the best mechanical performance when compared to decks with the same shear connection degrees.This is due to the fact that the relative slip and gap between the steel plate and the UHPC are minimized.