# Concrete curing method



## pilo0024 (Aug 22, 2006)

So after reading everyone's threads on fake rocks, there is something still unclarified for me. If each coat of cement is allowed to dry before adding the next, can it be made wet later to continue the curing process? I ask this because My cement has the polymer mixed in it, and that needs to dry out completely to cure, but obviously the cement cures wet.


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## pilo0024 (Aug 22, 2006)

one thing i should clarify is that I have a couple layers of grout down on my foam right now, and they did dry out completely. Am I stuck or can I re-wet them to get the curing going again?


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## melas (Oct 24, 2007)

Hydration and hardening of concrete during the first three days is critical. Abnormally fast drying and shrinkage due to factors such as evaporation may lead to increased tensile stresses at a time when it has not yet gained significant strength, resulting in greater shrinkage cracking. The early strength of the concrete can be increased by keeping it damp for a longer period during the curing process. Minimizing stress prior to curing minimizes cracking. High early-strength concrete is designed to hydrate faster, often by increased use of cement which increases shrinkage and cracking.

During this period concrete needs to be in conditions with a controlled temperature and humid atmosphere, in practice this is achieved by spraying or ponding the concrete surface with water, thereby protecting concrete mass from ill effects of ambient conditions. 

Properly curing concrete leads to increased strength and lower permeability, and avoids cracking where the surface dries out prematurely.

That said - I'm not sure how the the polymer mix would be effected by waiting until the first week of "wet" curing is completed to allow the concrete to dry out. 

Depending on the polymers added, the curing time should be greatly reduced - polymer modified concretes can reach near full strength in a matter of hours - I don't know what you have exactly but it is probably okay for the application . . . it definitely wouldn't hurt to continue keeping it wet for a while even after you've allowed it to dry out. As a side note - I used a polymer modified floor leveling cement for my rockwalls - I kept them wet/damp for the entire process and my concrete is HARD!

Matt


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## pilo0024 (Aug 22, 2006)

Matt that was some really helpful info. Thanks for taking the time. I'll def. be keeping it wet from the start in future attempts.


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