Push-out tests on three innovative shear connectors for composite cold-formed steel concrete beams

Abstract

The composite action between concrete and steel makes the use of composite beams in buildings more economical than the use of typical hot-rolled steel beams. This can be attributed to the beam's lower depth, which significantly reduces the weight of steel. Composite beams can be constructed by lipped C-channels made from cold-formed steel, concrete, and different shear connectors (which exhibit behaviours that are not yet well understood). In this study, the behaviour of three innovative shear connectors used in composite cold-formed steel concrete beams made of lipped C-channels with profiled metal decking was experimentally examined. Experimental tests aimed to determine the maximum resistance of the proposed shear connectors; these results were then compared with the predicted values and the values for other shear connectors investigated in other studies. Likewise, the ductility and the strength capacity of the shear connectors were investigated. Twelve push-out test specimens were prepared and tested in accordance with Eurocode 4. It was found that a shear connector's strength capacity considerably depends on its deformation and on the crushing of concrete. The ductile behaviour of all the tested shear connectors satisfied the ductility requirements of Eurocode 4. In this study, it is concluded that the proposed shear connectors were suitable for use in the construction of composite beams, as they were stronger than the standard headed studs and the other available shear connectors; they were also sufficiently strong to perform composite actions.