STUDY ON THE SHEAR RESISTING MECHANISM AND STRENGTH FOR AN INNOVATIVE COMPOSITE SHEAR CONNECTOR

This paper describes an innovative perfobond rib shear connector, which is welded with horizontal headed stud (denoted as composite connector hereinafter). Monotonic push-out tests of six specimens were carried out. Accurate nonlinear finite element models of the connector were established. A total of 216 push-out specimens were analyzed after they were calibrated against the experimental data in the scope of this study. Based on the experimental and numerical results, the shear resisting mechanism of the composite connector was analyzed. The results show that the composite connector has good shear resisting performance. Its shear strength, provided by the concrete dowels and horizontal headed studs, can be calculated by the superposition principle. The numerical results show that increases in the stud diameter and concrete strength would enhance the shear capacity of the composite connectors. The strength is increased by 27.7% when the stud diameter changed from 16 mm to 22 mm and increased by 20.6% when the concrete grade is changed from C30 to C50. The shear strength of the connector is affected slightly with an increase in the angles between the ribs. Several formulas of shear strength for the perforated rib shear connector and headed stud connector were estimated. Finally, a formula was proposed to predict the shear strength of a composite shear connector. This paper provides a reference for the application and further research of the composite connector.