Research on the shear behavior of PBL connectors in steel fiber reinforced concrete composite beam.

PBL (Perfobond Leiste) shear connectors are commonly employed in steel-concrete composite beams. In this study, the incorporation of steel fibers into concrete enhanced its mechanical properties, allowing PBL shear connectors to fully exert their shear performance. Through experiment and finite element simulation analyses on specimens, the influences of various parameters such as steel fiber content, steel fiber diameter, steel fiber length, diameter and length of the through reinforcement in the PBL shear connectors, plate thickness, diameter of openings, and the number of openings on the mechanical properties and failure modes of the specimens were investigated. The results indicate that the incorporation of steel fibers significantly improves the shear performance of concrete slabs and effectively restricts crushing and splitting. Compared with increasing the fiber diameter, increasing the fiber length can enhance the ultimate bearing capacity more effectively, and longer fibers have a more remarkable effect on restricting cracks. The diameter, length of the through reinforcement and the number of openings in the PBL shear connector have a relatively minor impact on the ultimate bearing capacity. Excessive openings will weaken the bearing capacity of the PBL shear connectors. Increasing the thickness of the PBL slab and the steel fiber reinforced concrete tenons have a better synergistic effect, which can significantly improve the shear performance of the specimens.