flaking concrete
flaking concrete
(OP)
my slab for my shop is 7 days old and is flaking. it was poured in 50-60 degree weather no rain on it for 2-3 days i live in texas so no freezing right now the land was dry before we poured it. the contractor is saying it was a bad mix and the concrete company is saying it was a good mix that its the contractors fault.there were 2 different trucks the first truck looks good the second is where the problem is. where the problem is the slab is a different color than the rest kinda a darker gray color. the concrete company came out today at the 7th day mark and did a hammer test or something to test the psi and said it was 2200 right now we ordered 3000psi any help would be appreciated





RE: flaking concrete
Hire an engineer to investigate this for you.
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RE: flaking concrete
RE: flaking concrete
The impact hammer they used on the slab is worthless for any meaningful data. To prove out the issue, you'll need a petrographic examination of the concrete. This is relatively expensive but can clearly show whether it is a mix problem or a construction defect.
RE: flaking concrete
RE: flaking concrete
1. Remove and replace the slab wherever it is blistered. This would require sounding the slab across all surfaces to find the bad areas.
2. By sounding the slab, identifying those areas that are poor - then mill down the top surface of the slab (perhaps 1 1/2" min.) and put back a 1 1/2" thick bonded overlay slab.
Option 2 is probably more expensive than option 1.
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RE: flaking concrete
Option 3 isn't what you paid for and is a diminished quality slab.
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RE: flaking concrete
RE: flaking concrete
RE: flaking concrete
Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
www.americanconcrete.com
RE: flaking concrete
If spalling is not an issue then you can 'patch as you go' or check the entire slab for delamination and fix it all. Areas of delamination can be determined by chain drag, or other means.
You likely did not get good value and subject to over wetted aggregate, it is very likely a finisher problem.
Dik
RE: flaking concrete
Mike McCann, PE, SE (WA)