Method of determining rebar (As) in composite slab

[Iasonasx]

Is there a method to determine the amount of steel necessary in a slab? I have done this a couple of years ago but I totally forgot the method I followed. One thing that comes to mind is to consider that like we do the method of designing top steel in beams. But is there a set of tables to use or something simpler?
Thank you

 

[jerseyshore]

What kind of slab? SOG or structural slab?

 

[Iasonasx]

I see no reason for a slab to be composite if it is on grade. My question is about determining the necessary steel in a composite slab.

 

[BulbTheBuilder]

I can't remember the exact reference as it was two years ago, but I think SDI has composite steel deck publication. It showed span configuration with moments and deflection formulas, so you got to work out your As. I think ASC steel deck or Vulcraft has a table with decks and WWR (WWF) called out, so you pick one which works for your load. No sure but check these and see if you find any info.

 

[BridgeSmith]

For slabs on beams/girders continuous over interior supports, i.e. where there's negative moment and tension in the slab, AASHTO has several provisions that apply. The most prominent one is that the slab must include a minimum area of longitudinal reinforcement equal to 1% of the slab cross section, and 2/3 of that 1% has to be in the top layer. For composite slabs, that area of steel has to extend to a point beyond where the tension stress in the slab is < 0.9 Fr (concrete tension rupture stress).

 

[jayrod12]

You need to provide reinforcing wherever the concrete will be in tension. So that would be perpendicular to all composite joists/beams along the entire length of all, and parallel to the joists/beams where they may be continuous over their supports.

 

[jerseyshore]

Sorry didn't see in the subject that it said composite. Generally I do what BTB mentioned about using the Vulcraft catalog with the specified reinforcing.