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Just ran the numbers on slab curling from my last job
Found out a 6-inch slab can curl up to 1/8 inch at the edges if you don't wet cure for at least 7 days. Caught this in a PCA tech brief, and it explains why two of my driveways had those hairline cracks near the joints last year.
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richard_ramirez13d agoProlific Poster
Changed my mind completely after seeing it firsthand on my own driveway last year.
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rileygonzalez14d ago
Yeah that PCA tech brief is pretty solid. I remember reading something similar from ACI about how temperature changes also mess with the curling, especially when you pour in the middle of summer. The top dries way faster than the bottom and that's where the curling starts. The 1/8 inch thing sounds about right from what I've seen too, but it gets worse if you don't have proper joints cut in. I actually watched a video from a concrete contractor where he showed how wet curing with burlap and plastic for a full week cut down his callbacks by like 80%. And don't even get me started on how many guys skip the curing just to save a few bucks on labor then wonder why their slabs crack later.
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