*
Pouring a driveway. Two camps are butting heads. One crew always puts a sealer on the day after the pour. they run two crews–one that pours and one that cleans up and seals. The other camp is insisting that the sealer/retarder be applied w/in 2 hours of pouring.
What will be the difference to the concrete?
Thanks. Jim
Replies
*
Jim,
There are curing compounds, cure & seal compounds, membrane and non-membrane compounds. A retarder is added to the concrete mix to slow the hydration process. These are usually used only in mass pours or with "hot" mixes that may generate too much heat while curing and cause cracking.
Having said that, it is important to cure/seal the surface as soon as the finishers are done and the surface has formed a "skin". This will conserve the most moisture in the slab, which is why you're doing this in the first place. If you're using a simple non-membrane cure, you'll still want to keep the slab damp or covered with visqueen. A membrane cure will usually eliminate the need for the visqueen. A cure and seal will give a shiny coating to the surface and eliminate "chalking".
It's not a bad idea to have the clean-up crew chase the tooled control joints with a Partner saw. Most finishers joint tools are worn and just put a dent into the surface, rather than creating a weakened plane for shrinkage cracks to form in. The purpose of the control joint is so the crack will occur inside the joint. Unless it is a least an inch deep on a four inch slab the crack may wander out of the joint and across your slab. It's worth paying a little extra for.
Eric
*Thanks Eric. I've been educated.
*
Pouring a driveway. Two camps are butting heads. One crew always puts a sealer on the day after the pour. they run two crews--one that pours and one that cleans up and seals. The other camp is insisting that the sealer/retarder be applied w/in 2 hours of pouring.
What will be the difference to the concrete?
Thanks. Jim