Precautions for pouring in Colder weather

[nu guy ky]

Thanks For the help on the other two questions I had posted last week
We are suppose to Break ground so to speak With the footers next week

Now It is starting to Get Colder at night time 35-40 Degrees
Had Frost a few times My Question I’d like to ask
When They pour the floor and footers ..
Dose it set up the same In colder Temps I’m going
Out on a Limb here ..i DON’T RECALL Where I heard this
But when Temps are like this shoild they Add Calcium
Dose that sound right ..

This Is where I’m Thinking I heard this My Nephew had a Drive Poured
lasty yr In the spring The Temps Were Nuts It was getting down To and below freezing at Night
The Temps In the day were Above Norm ...

He had it poured and within a few days He started to see Cracking
Now it seems someone told me The company should have added something In the Mix To
help keep this from happening at that time of yr... I thought they said Calcium

Dose that sound right ....

Thanks for any input

 

[Willy Victor]

I think you're looking for calcium chloride.


Willy

 

[brad d]

Yeah calcium speeds up the cure.. but I hear its not the best if you have rebar in the concrete, for it can make it rust??

Best bet is to pour ASAP and use some insulated tarps or thick poly with 4" of hay on top. This will keep the heat in over night.

Im in the same boat as you... but my shop is on a grade beam so I can build then close it up.. add some heat and pour.

 

[Bigger Hammer]

If it isn't actually freezing at night I wouldn't spend the money on blankets or anything like that. throw a dose of non-chloride accel. in the mix to speed up the initial cure. The concrete supplier is most likely into winter conditions this time of year (which you pay for whether you like it or not) so hot water will most likely be automatic.
Around here (Indy) we won't mess around with any blankets until it hits below 28-30 degrees. The concrete won't freeze due to it producing enough heat itself to keep it from freezing.

 

[nu guy ky]

thanks for all the feedback

That is Prob was the case with my nephew's drive the ground still froze temps
still getting down to freezing at night ...

one more question
I’m going to add Commercial fiber to the mix as well
3500 lb along with wire mesh ...Should there also be a need for rebar
or would this be over kill /If so on pad of 28x 30
how sould the rebar be placed {spaced}Is there a rule
It will be monolith pour 5 inches

Thanks again for the help