Flexural strength test on new profiled composite slab system

Abstract

This research presents an experimental study on the flexural strength and failure behaviour of a newly developed composite metal decking system. The newly developed metal decking system with a thickness of 0.75 mm and 1.0 mm produced by the industry requires a detailed study in strength and performances before it is launched for commercialization. A simply supported conventional reinforced concrete slab is used as the control specimen and two composite slabs with different metal thickness of steel sheet profiles were constructed and tested under a four points flexural strength test. The strength and behaviour of the slabs are recorded and comparisons with conventional slabs with composite deck slabs are made to achieve the objectives. The recorded results of three different slabs were then used to plot a load-displacement graph and deflection profiles are to be analysed and compared. The yield flexural capacity and average yield displacement of specimens for the composite slabs were 28.0 kN and 0.80 mm respectively. The 1.0 mm metal thickness composite slab has the highest ultimate flexural capacity among all specimens which is 84 kN followed by a 0.75 mm metal thickness composite slab with 58 kN and ends with the lowest 9.1 kN of conventional slab. Two cracking patterns were found during the experimental test which includes shear cracking and flexural cracking`. Besides that, two major failure modes under bending which are flexure failure at the centre point of the specimen and bond or longitudinal slip failure along the side of the specimen were found in the experimental test. Bond failure results in slippage between the concrete and metal deck, which can result in cancellation of the composite action at interface. In conclusion, the strength of slabs improved, and ductility was remarkably increased when slabs acted as a composite structure.