Finishing concrete can be a
tricky operation. Our technical services department
has come up with ten tips to take the guesswork
out of concrete practices so you can complete a
professional job the first time and every time.
By using these 10 tips, you can avoid common errors
and misconceptions and the resulting problems that
cause construction delays and cost you money while
creating a professional job that exceeds your customers
expectations.
1. To avoid settlement cracking you should ensure
the highest quality sub grade possible (be certain
it is properly compacted).
2. Please check and re-check the depth of your
slabs, this can eliminate the wait needed for another
concrete mixer, to arrive at your jobsite.
3. Do not use an impermeable vapor barrier under
concrete that will be exposed to ambient conditions.
4. Air entrainment should only be used in exterior
concrete, unless it will be exposed to freeze thaw,
or sulfate attack.
5. A steel trowel should never be used on concrete
that is entrained with air, it can trap bleed water
and bleed air, which causes delaminating.
6. Remember to place your concrete with as little
extra water as possible. Concrete only needs enough
water (approximately a 1 inch slump) to hydrate.
Any extra water is merely water of convenience,
and the more water added the weaker the concrete
becomes.
7. Try to avoid finishing operations if bleed
water is still in or on your concrete, this will
weaken and hinder the performance of your concrete
surface.
8. Please try not to add more than 2% calcium
accelerator to your concrete. A rule of thumb is
no more than 2 bags of calcium per 10 yard load.
9. Please try to avoid placing concrete in high
wind conditions, for it can institute a series
of plastic shrinkage cracks, due to the rapid loss
of surface moisture in your concrete.
10. Remember that the curing process is just as
important as any other step in your concrete pour.
It aids in strength gain, crack control, improved
durability, better serviceability, and appearance.
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