John and Towertalkians:
Concrete does indeed cure by the process of hydration
but it has actually more water than it needs to cure.
The reason you wet cure is to prevent the reduction of
surface strength by too rapid of a cure or drying at the
air/concrete surface relative to the rest of the
concrete mass and reduction of heat. This helps to
prevent micro surface cracks in the concrete. Concrete
does not absorb water in the curing process.
Those interested should go to this url for a primer on
concrete, placing and curing:
http://www.portcement.org/cb/concretebasics_concretebasic
s.asp
Someone else talk about asking for more bags in the mix
to get larger rock therefore more strength. Actually
bags refer to the cement ratio of the mix. The more sacks
(bags) of cement the higher the strength to a point.
Larger rock does not mean higher strength.
The above mention url is a very good place to get a
basic understanding of how concrete really works and how
the components interact.
All the Best
Hank Lonberg, S.E.,P.E. / KR7X
Lonberg Design Group
> on 10/3/02 10:26 PM, EUGENE SMAR at spelunk.sueno@prodigy.net wrote:
>
> > Concrete cures almost forever. That is, it is ALWAYS getting stronger. The
> > trick is to wait until it's strong enough to support your antenna load.
>
> Not to nitpick, but I disagree. Concrete cures by a process called
> hydration. This involves moisture being absorbed into the concrete. That's
> why it's best to keep concrete covered in plastic for a week or so after
> being poured. The moisture is what keeps the hydration process going. Once
> the moisture is removed and the concrete completely dries, the hydration
> stops and won't continue ever again. The concrete won't get any stronger at
> that point.
>
> If you can constantly and forever keep the concrete damp or in water, it
> will harden forever so your statement is not entirely incorrect.
>
> 73,
>
> Jon
> NA9D
>
>
>
> -------------------------------------
> Jon Ogden
> NA9D (ex: KE9NA)
>
> Life Member: ARRL, NRA
> Member: AMSAT, DXCC
>
> http://www.qsl.net/ke9na
>
> "A life lived in fear is a life half lived."
>
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