Experimental study on bearing capacity of PBL shear connector group in hybrid structures

The shear transfer of steel-concrete joint sections directly depends on the bearing capacity of shear connector groups in hybrid structures. The static tests on 9-type 18 specimens of multi-row perfobond rib shear connectors (PBL) were conducted to investigate the bearing capacity of PBL shear connector groups. On the basis of the load-slip distribution on a single shear connector, the slip distribution and load characteristic of PBL shear connector groups in the whole loading process were studied. The slip distribution rules among multi-row shear connectors were analyzed, and a calculation method for the bearing capacity of PBL shear connector groups was proposed by adding up the loads corresponding to the slip distribution of the PBL shear connector. In addition, the load index in serviceability limit state was presented according to the statistical results of a great amount of experimental data. Experimental results show that the load-slip relation of a single PBL shear connector in the hybrid structure can be expressed in the form of asymptotic Buttry curve, and the slip characteristics among different rows of PBL shear connectors follow quadratic curve distribution. Meanwhile, the load corresponding to 0.2 mm average slip of the PBL shear connector group is recommended as the ultimate load in serviceability limit state for a PBL shear connector group. The proposed analytical method on the bearing capacity of PBL shear connector groups efficiently overcome the defects in current calculation method and it is proved by the experimental results.