concrete

thedeeredude · October 29, 2005, 09:36:11 PM

Now it's a concrete question :

Should we use regular quikrete, or the quickset formula? Its around 50-60 during the day and will dip down to lower thirties at night. What is average cure time for these two formulas in a 10" sonotube? Thanks

Don P · October 30, 2005, 09:58:37 AM

I'm certainly no concrete expert but I'm procrastinating doing some today, a little under a deck with the regular mix. Our weather is about the same. Soil is still warm and concrete produces heat as it cures. I've wrapped stone piers in sacks, tarps and plastic to help insulate them through marginal weather like this. As long as it doesn't freeze too hard that will get you through. I leave it wrapped as long as possible. I guess 7 days would be considered minimum, 28 would be "fully" cured although I've been told concrete cures for 40 years or so? Our masons have worked on a chimney all week and will pop through the roof tomorrow. We did have a slab poured once with a 0F night. A high early, warm water, air entrained, fibermesh mix and quilts over the slab after it was finished. Part of the slab had to be cut out later (bozo plumber) and it was fine, there was no spalling and the crew was cussing and working hard. When Dad was in Russia pouring in very early spring, they laced fine wire through the pour and hooked it to an AC welder on a low output to add some heat.

Raphael · October 30, 2005, 10:31:48 AM

I'd go for the regular quikrete, presumably the sonotube extends below the expected frost level and will act as a heat pipe protecting it from a hard freeze. A little overnight protection on the exposed end for the first week or so will set you up fine. Black plastic on the ground adjacent to the tube will help capture heat from the sun and speed the curing process (insulate w/ straw overnight).
The collumn should be safe to work with about 36-48hrs after the pour assuming the concrete was mixed properly.

ScottAR · October 30, 2005, 12:21:27 PM

I wouldn't use the quikset for anything important. Somthing in the mix gathers moisture way quicker. At my old job, we would find semi hard sacks at the bottom of the pallet. This was in a climate controlled building. :