Push-out test of hybrid shear connector in steel-precast UHPC composite slab

Abstract

This paper presents an experimental investigation on the shear behavior of steel and Ultra-high Performance Concrete (UHPC) composite slab connected by different connector types including epoxy resin adhesive, headed stud, and their hybrid. Thirty-two push-out tests were conducted and the failure mode and load-slip cure of specimens were tested. The influences of parameters including the connector type, bonding area, number of headed studs and loading mode on the shear resistance of hybrid connector were explored. The shear transfer mechanism, composite effect and shear resistance of the stud and epoxy resin adhesive for hybrid connector were discussed. The epoxy resin adhesive and headed studs in hybrid connector showed steel interface debonding and stud shrank failures. The ratio of shear resistance for studs to epoxy resin adhesives exerted a great influence on the slip performance and shear resistance of hybrid connector. The composite effect depends on whether the studs bear the load firstly. An equation was proposed by taking factors including the composite effect and loading mode. The predict results showed high correlation with the experimental ones.