Concrete On Metal Deck Slab

Concrete slab on metal deck cracking.

Concrete on metal deck slab.

Composite slabs consist of profiled steel decking with an in situ reinforced concrete topping. Composite steel deck is a permanent concrete form and provides positive reinforcement while it eliminates the time and cost of wood forming. They don t have any real design guidance concerning deflection or crack control or how the tolerances can be different between the concrete and the steel. The decking not only acts as permanent formwork to the concrete but also provides sufficient shear bond with the concrete so that when the concrete has gained strength the two materials act together compositely.

The requirements for shoring are based on the ability of the decking to sustain the weight of the fresh concrete plus a construction live load of 20 pounds per square foot without exceeding an allowable unit stress of 20 000 psi. Composite floor decks have embossments that grip the concrete slab and they are typically reinforced with rebar or wire mesh which creates a strong bond with the concrete floor. Casting the slab in strips parallel to the joists would eliminate negative moment cracking over the beams since the concrete would not have set and over the columns there would be a nice straight joint. The shear capacity of the composite deck alone is added to the beam shear capacity of the concrete to arrive at the total beam shear capacity of the slab.

Engineers who design slabs on metal deck aren t thinking about the contractor. Slab thickness is measured from bottom of ribs. 3 composite floor deck panels are primarily used for pouring concrete slabs. The convention in design of composite deck slab systems is to use the transformed section to convert the area of steel into an equivalent area of concrete.

The transformed section properties are then used to determine the nominal bending moment and predicted deflections for the composite deck slab section. As a contractor therefore don t be afraid to talk to the engineer about all this. Galvanized corrugated steel deck sheets for concrete slab yx51 250 750 is one kind of bondek sheets for multiple high rise buildings which is also called steel floor decking or bondek slab our quality composite decking sheets have full set of technical support. Composite floor decks are available in 1 1 2 2 or 3 depths.

This approach to suspended concrete slab construction is very common in commercial construction. Composite floor decks are mostly used to create a composite structure with the concrete slab that is poured upon it.