Shear behavior of stud and SFCBs-reinforced PBL composite connectors in steel-concrete structures

In order to fully utilize the advantages of stud and perfobond leiste (PBL) connectors, a new composite shear connector was proposed in which the studs were welded to the H-beam of the PBL shear connectors. In addition, to further improve the durability performance of the structure, steel-fiber-reinforced polymer composite bars (SFCBs) were used to replace steel rebars as penetrating rebars. In this study, the shear behaviors of SFCBs-reinforced composite shear connectors were investigated by push-out tests. The effects of the number of studs, the number of holes, and the type of penetrating rebars on the failure mode, load-slip curve, and shear behavior of the composite shear connectors were analyzed. The specimens' failure modes were mainly shearing the studs and crushing the concrete. Increasing the number of studs and holes has resulted in an increase of at least 7.47% in the shear resistance and 12.36% in the stiffness. SFCB had little effect on the shear resistance and reduced the stiffness but could improve ductility, with a maximum improvement of 11.49%. Additionally, a finite element model was established for parametric analysis. The results showed that the diameter of the SFCB and hole had a significant impact on the shear resistance. An equation for calculating the shear resistance based on the contributions of various components has been established that was applicable to composite shear connectors and has good accuracy and applicability.