Composite metal deck and slab

[TedEP]

Is WWF required/needed for temp and shrinkage in an elevated slab designed using composite deck? It is not needed for carrying load for the values in the deck manufacturers tables for composite deck (at least for Vulcraft). My situation is 1.5VL20, 5" overall tk. Thanks for the help.

 

[spats]

According to the SDI Specifications for composite steel floor deck, "Temperature and shrinkage reinforcement, consisting of welded wire fabric or reinforcing bars, shall have a minimum area of 0.00075 times the area of concrete above the deck, but shall not be less than 6x6 - W.14 x W1.4 welded wire fabric".

 

[spats]

Oops! Correction: "... shall not be less than the area provided by 6x6 - W.14 x w1.4 welded wire fabric."

 

[JLNJ]

Just because you put concrete fill on the deck doesn't mean you need to reinforce it.

If the deck can carry your loads and is galvanized such that you are confident that it will be permanent, I don't see why you couldn't use plain concrete.

 

[spats]

JLNJ,

I don't know why you're fighting against using the prescribed T&S reinforcement specified by the SDI. It's not specifically part of the code, but under what other specific set of circumstances would you deem T&S reinforcement is not required for concrete, based on your "judgement"? This is composite deck, and the concrete helps carry the load, not just the deck. Sounds like you were unaware of the requirement, and are trying to justify past designs where you did not provide reinforcement. Either that, or you don't know what composite deck is.

 

[nevsam12]

If you do not provide reinforcement near the top of slab at the supports, slab has potential to crack due to negastive BM at the support. And those cracks can be ugly.