# contractor poured air entrained for pole barn slab



## mrcat (Jun 27, 2015)

NYCB said:


> I usually specify "no air" for my floors, and of course they still ad air to it, but at a much lower amount. One supplier I use has special mix designs based on application, so they always ask what you are pouring when you order.
> 
> 
> 
> I don't pay much attention to the percentages.


I always used to ask for "no air", but one of the dispatchers at Hansen told me if it's a garage floor they are going to put air in it anyway. 
They always ask what I'm pouring, so I just specify "low air" now.


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## Fishindude (Aug 15, 2017)

After looking at the pics, it looks like "crazing" to me.
This does not typically affect the structural integrity of a slab.

Never a bad idea to have the ready mix supplier rep come take a look and get their two cents worth.


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## NYCB (Sep 20, 2010)

mrcat said:


> I always used to ask for "no air", but one of the dispatchers at Hansen told me if it's a garage floor they are going to put air in it anyway.
> They always ask what I'm pouring, so I just specify "low air" now.
> 
> 
> Sent from my SM-G930V using Tapatalk


Hanson never asks me, they usually just ship it with air unless I tell them otherwise (and I do tell them otherwise because we've gotten floors with air in them).

Robinson will always ask what you are pouring and batch it accordingly.


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## griz (Nov 26, 2009)

WOW, i don't get how some of you guys work.

the batch plant DOES NOT TELL ME what mix design i need...

I TELL THEM EXACTLY WHAT I WANT...

if the batch ticket does not match what i ordered, the load goes back. 

I'm building to pre-determined specs and my contract does not allow me to deviate without an approved RFI...


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## Mike-B (Feb 11, 2015)

I don't remember ever seeing a spec for a slab on grade that did not include at least 3% air. Most of what I see calls for 5-6%%.

Looks like the finishers may have let it get away from them a bit and added some water to the surface in order to complete the finishing process. Just a guess based on the color variations.


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## NYCB (Sep 20, 2010)

Mike-B said:


> I don't remember ever seeing a spec for a slab on grade that did not include at least 3% air. Most of what I see calls for 5-6%%.
> 
> Looks like the finishers may have let it get away from them a bit and added some water to the surface in order to complete the finishing process. Just a guess based on the color variations.


There's a few articles you can find floating around about finishing air entrained concrete, and that's pretty much what you have to do in order to not peel it.

Get it floated, and let it get tighter than you normally would, then get the steel on it and splash it a bit.

I think most guys have learned that from experience anyway, nothing worse than those first couple passes on a floor with air and having big clods come up off the surface because they are stuck to your shoes.


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## jomama (Oct 25, 2008)

I know this is a month old, but it's undoubtedly "crazing" shown in the images. Generally, not an issue other than aesthetically. If you're worried about it possibly delaminating, drag a log chain over it and listen for a "hollow" sound in spots. If you hear that, then you have something to worry about.

As for air entrainment, all concrete has what's called "natural air", which naturally occurs due to the mixing process, and is generally around 2% when tested.

We almost always pour "half air" mixes on power trowelled floors, which is about 3.5-4% air. Really cut's down on finishing sandy grit due to excessive bleed water.

We poured and finished full air (~6%) on hard trowelled floors here for years, mostly due to ignorance. Most basements floors were just fine (other than excessive cream pickup on shoes, tools, etc.. that NYCB mentioned above) but get a floor outside in the sun with some wind and low humidity, watch out, it would be become a crap-show real quickly.....


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