Mechanical behavior of lightweight concrete steel deck

This paper presents the structural behavior and failure mode of lightweight concrete (LC) steel decks with varying interfaces between concrete and steel decking. Two types of concrete (lightweight and normal) steel deck specimens having the same dimensions but differing interface treatments are investigated through a four-point bending test setup. Each type of concrete steel deck is designed to three interfaces – screw at spacing of 15 cm, 30 cm and without screw between concrete and steel. The results showed consistent behavior between lightweight concrete steel deck and normal concrete (NC) steel deck, both of which presented a steep drop in load after the first peak load, followed by a smooth rise until the ultimate load, which exceeded the initial peak load, was reached. The increase of screws on the interface between concrete and steel decking increased the load capacity and ductility. The first peak load of the concrete steel deck was close to the value calculated by a proposed method based on the working stress design method, with a deviation under 18%. The first peak load of the concrete steel deck can be considered as the load capacity of the concrete steel deck and can also be evaluated by the proposed method.