Comparison of various shear connectors for improved structural performance in CFS concrete composite slabs

Composite sections comprising of wisely selected materials has gained popularity in the construction industry, as it may result in utilizing the advantages of two different materials thus resulting in efficient sections, which will not only reduce the dead loads but also provide economical solutions. Cold-formed steel (CFS) concrete composites have been used extensively in building construction, as the inherent weakness of local buckling in the CFS sections under compressive loading is taken care of by the concrete, which has significant compressive strength. This study presents an experimental investigation performed on full-scale simply supported CFS concrete composite slabs under four-point monotonic loading, with an aim to evaluate the effectiveness of the different shear connectors being adopted. The shear connectors were so adopted that they could provide the least possible interaction (for representing the no-interaction condition), partial-interaction and full-interaction between the steel deck sheet and the concrete slab. The performance of the various shear connectors was assessed in terms of strength, stiffness and ductility ratio. Cracking as well as end slippage were also studied. The test results were compared with a conventional RC slab, in terms of structural performance as well as cost and strength-to-weight ratio. The flexural test strengths were compared with the design strength quantified using the Euro Code. The degree of shear interaction was also investigated. It was found that the CFS concrete composite slabs not only performed better structurally but economically as well, in addition to providing significant strength-to-weight ratio, when compared to a conventional RC slab.