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Concrete mix for exposed exterior slab on grade

Concrete mix for exposed exterior slab on grade

Concrete mix for exposed exterior slab on grade

(OP)
Party pavilion, open 4 sides, wood trusses on columns at roof. Location in IL (frost and snow). My question is about my slab on grade mix design. I have the following:

Min f'c = 3000 psi.
Min cement. Material = 520 lb/cubic yd.
Max W/C = 0.40
Slump = 4" + - 1"
Air content = 5.5% + - 1

This is the typical SOG design we use for interior slabs. Should I change anything for the exterior use?

RE: Concrete mix for exposed exterior slab on grade

Slump 3" max, air 5% to 7%, f'c (if exposed to deicing salts) 35 MPa.  Your cement content and W/C will likely achieve this.

Dik

RE: Concrete mix for exposed exterior slab on grade

It's going to be very difficult to get a workable mix if anyone is enforcing the .40 w/c with such little cement. I doubt you even have 3" slump. Why not use 3500 or 4000 psi?

Broom finish?

Why are you using 5.5% air for an interior slab?  

RE: Concrete mix for exposed exterior slab on grade

(OP)
VTEIT:

Yes its broom finish. Now that you mention it, 5.5% does seem high for interior, should be more in the range of 3% I think. But 5.5% should be good for exterior, right?

RE: Concrete mix for exposed exterior slab on grade

I thought that if it was open on 4 sides, it would pretty much be exterior... and not interior.  5.5% may be a bit on the low side, depending on what is delivered and if this is max/min.  In Canada, we often spec 5% to 7%.  3% is in the upper range of entrapped air and way too low for frost resistance...

Dik

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