Composite Deck T&S Reinforcement Placement

[engjg]

Anyone aware of code requirements or industry recommendations on placement of temperature and shrinkage steel WWR for composite deck. SDI seems to defer to CRSI but I can't seem to find any document from them that addresses.

 

[jayrod12]

Shouldn't your T&S reinforcement be considered top reinforcement in that situation to minimize crack width at the expose face?

 

[JAE]

If you look at the SDI Standard for Composite Floor Deck (ANSI/SDI-C1.0) it states that welded wire reinforcement or bars should have a minimum area of 0.00075 x Concrete Area above the deck (per foot) but not less than 6x6-W1.4xW1.4. Suggested 3/4" to 1" clear from the top.

They also state that fiber reinforcement can be used as well.

Check out Eng-Tips Forum's Policies here:
faq731-376

 

[engjg]

Thanks JAE. I found it it the 2006 version of the that document but it appears they removed it in the 2017? How often do you see WWR draped in practice?

 

[jayrod12]

Never

 

[JAE]

Never

Check out Eng-Tips Forum's Policies here:
faq731-376

 

[engjg]

If 3/4" or 1" is recommended industry practice...it seams like the FDDM design examples for concentrated load evaluation of weak axis bending distribution steel is out-of-sync... as they assume 1/2 the slab depth placement.

For a common 3"slab over 2"deck w/ minimum T&S WWR, a d=0.75" vs. d=1.5" yields a significant difference in capacity...

 

[JAE]

engjg,
We typically show the WWF in the center or at least a bit above the center of the net slab thickness (that portion above the top of the flutes).

We also call for #4 bars, about 4 ft. long or so, oriented perpendicular to the major interior girder beams as you typically get flexural induced cracks along those beams.

Don't ever drape WWF although I suppose if you emphasized it on your plans, showed exactly how to chair it, etc. you might get a contractor that would properly perform for you.



Check out Eng-Tips Forum's Policies here:
faq731-376