That's wrong. Concrete is stronger when mixed with less water.
I received a private reply from someone who does this for
a living. He said that you won't get much mixing pouring
under water. Therefore, your method is ok, not because
it's ok to mix concrete as loose as you want.
See: http://matse1.mse.uiuc.edu/~tw/concrete/prin.html
Strength of Concrete
"The strength of concrete is very much dependent upon the hydration reaction
just discussed. Water plays a critical role, particularly the amount used.
The strength of concrete increases when less water is used to make concrete.
The hydration reaction itself consumes a specific amount of water. Concrete
is actually mixed with more water than is needed for the hydration
reactions. This extra water is added to give concrete sufficient
workability. Flowing concrete is desired to achieve proper filling and
composition of the forms. The water not consumed in the hydration reaction
will remain in the microstructure pore space. These pores make the concrete
weaker due to the lack of strength-forming calcium silicate hydrate bonds.
Some pores will remain no matter how well the concrete has been compacted. "
73,
Tom
----- Original Message -----
From: "Jim White" <k4oj@tampabay.rr.com>
To: "Tom Wagner" <tom@n1mm.com>; <towertalk@contesting.com>
Sent: Sunday, July 07, 2002 11:57
Subject: Re: [Towertalk] Hit water digging hole - advice?
> SAY WHAT?
>
> It will just take longer for the concrete to cure - which is an wonderful
> thing! The ultimate strength of concrete is greater the longer it takes
to
> cure - during the initial phases of curing you will see concrete being
> spritzed with water and hay placed on it to try and keep more of the
> moisture on the concrete....during the first few days after pouring many
> spray the concrete with water again - no sense in rushing things....the
> ideal or ultimate concrete would NEVER cure!
>
> Basically the concrete will displace the standing water...you will end up
> with a little thinner mix but not worth mentioning - where you will notice
> it is on the very top of the pour when you go to finish the concrete....do
> not fret....it is gonna be fine.
>
> K4OJ
>
> ----- Original Message -----
> From: "Tom Wagner" <tfwagner@snet.net>
> To: <towertalk@contesting.com>
> Sent: Sunday, July 07, 2002 10:13 AM
> Subject: Re: [Towertalk] Hit water digging hole - advice?
>
>
> > If you stab the concrete with a shovel with a foot
> > of water on top, won't you mix the water into
> > the concrete?
> >
> > Excess water makes concrete weak.
> >
> > Tom - N1MM
> > ----- Original Message -----
> > From: "Jim White" <k4oj@tampabay.rr.com>
> > To: "Tom Wagner" <tom@n1mm.com>; "David" <k4zzr@bellsouth.net>;
> > <towertalk@contesting.com>
> > Sent: Sunday, July 07, 2002 10:06
> > Subject: Re: [Towertalk] Hit water digging hole - advice?
> >
> >
> > > As the concrete is going in I always continuously stab the pour with a
> > round
> > > point shovel - just to make sure there are no voids created...
> > >
> > > I really doubt you need worry about pumping the water - the concrete
> WILL
> > > displace it - "been there done that" - the displaced water however
needs
> > to
> > > be guided to wherever you want it guided to - or - the alternative is
to
> > > pump it to where you want it to end up....fortunately the few pours I
> have
> > > had water in the hole were in locations near a suitable dumping ground
> for
> > > the overflowing water and a trench was simply dug to aid in pointing
it
> in
> > > the right direction...
> > >
> > > K4OJ
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > ----- Original Message -----
> > > From: "Tom Wagner" <tfwagner@snet.net>
> > > To: "Jim White" <k4oj@tampabay.rr.com>; "David" <k4zzr@bellsouth.net>;
> > > <towertalk@contesting.com>
> > > Sent: Sunday, July 07, 2002 9:51 AM
> > > Subject: Re: [Towertalk] Hit water digging hole - advice?
> > >
> > >
> > > > I'm sure the driver of the concrete truck will have seen
> > > > this before. Offer him some money to help you pour, and
> > > > you'll get his advice for free.
> > > >
> > > > My guess is that Jim is right, but I'd think about pumping
> > > > the water out after you have put a foot or two of the
> > > > concrete in. You'll want to punch down the concrete to
> > > > get the air out long before the hole is full. Have you ever
> > > > pushed a 2x4 through 6' of concrete?
> > > >
> > > > Just make sure you have a pump on hand that can clear
> > > > the hole in 5 min or so. Then you have options.
> > > >
> > > > 73 & gl,
> > > >
> > > > Tom Wagner - N1MM
> > > > Check out the N1MM Free Contest Logger at
> > > > http://www.N1MM.com
> > > > http://groups.yahoo.com/group/N1MMLogger
> > > > No Yahoo membership required.
> > > >
> > > >
> > > > ----- Original Message -----
> > > > From: "Jim White" <k4oj@tampabay.rr.com>
> > > > To: "David" <k4zzr@bellsouth.net>; <towertalk@contesting.com>
> > > > Sent: Sunday, July 07, 2002 09:36
> > > > Subject: Re: [Towertalk] Hit water digging hole - advice?
> > > >
> > > >
> > > > > I would leave it alone....sounds like it is slightly oversized
> > > > already....as
> > > > > far as aesthetics goes - be prepared to form a "top" where the
slab
> > > > extends
> > > > > above the ground....I would not pump any standing water out - I
> would
> > > let
> > > > > the concrete displace the water - be prepared for the "run off" as
> it
> > is
> > > > > kicked out of the hole by the concrete.
> > > > >
> > > > > 73, GL
> > > > >
> > > > > Jim, K4OJ
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > From: "David" <k4zzr@bellsouth.net>
> > > > > To: <towertalk@contesting.com>
> > > > > Sent: Sunday, July 07, 2002 9:03 AM
> > > > > Subject: [Towertalk] Hit water digging hole - advice?
> > > > >
> > > > >
> > > > > > We dug the 5'x5'x6' hole for the tower Saturday and have the
> > concrete
> > > > > truck
> > > > > > coming Monday morning. QTH is south Florida, soil is a dark
loamy
> > > > > > consistency with plenty of sand content. The sides seem to be
> > holding
> > > > up
> > > > > > and the moment . We didn't notice that we had hit the water
table
> > > until
> > > > > we
> > > > > > were almost 6' down because it was just a trickle. I checked
the
> > hole
> > > > > this
> > > > > > morning and I've got a full foot of water in the bottom now.
I'm
> > > > worried
> > > > > > the sides might start caving in between now and tomorrow. I
> > figured
> > > I
> > > > > > would pump out the water when the concrete truck gets here, but
> now
> > I
> > > > > wonder
> > > > > > if I should try to keep pumping it out between now and Monday or
> > just
> > > > > wait.
> > > > > > One thought is that if I pump out the water now, the spot water
> the
> > > > water
> > > > > is
> > > > > > coming in might eat away at the sandy soil even more as it
refills
> > the
> > > > > hole,
> > > > > > the other thought is that I should pump it out now so it doesn't
> > > soften
> > > > > the
> > > > > > four sides and cause them to fall in. Obviously, any QUICK
> > thoughts
> > > or
> > > > > > suggestions would be most welcome.
> > > > > >
> > > > > > 73,
> > > > > > David, K4ZZR
> > > > > >
> > > > > >
> > > > > > _______________________________________________
> > > > > > Self Supporting Towers, Wireless Weather Stations, see web site:
> > > > > http://www.mscomputer.com
> > > > > > Call 888-333-9041 to place your order, mention you saw this ad
and
> > > take
> > > > an
> > > > > additional 5 percent off
> > > > > > any weather station price.
> > > > > > _______________________________________________
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> > > > > > Towertalk@contesting.com
> > > > > > http://lists.contesting.com/mailman/listinfo/towertalk
> > > > > >
> > > > >
> > > > > _______________________________________________
> > > > > Self Supporting Towers, Wireless Weather Stations, see web site:
> > > > http://www.mscomputer.com
> > > > > Call 888-333-9041 to place your order, mention you saw this ad and
> > take
> > > an
> > > > additional 5 percent off
> > > > > any weather station price.
> > > > > _______________________________________________
> > > > > Towertalk mailing list
> > > > > Towertalk@contesting.com
> > > > > http://lists.contesting.com/mailman/listinfo/towertalk
> > > > >
> > > >
> > >
> >
> > _______________________________________________
> > Self Supporting Towers, Wireless Weather Stations, see web site:
> http://www.mscomputer.com
> > Call 888-333-9041 to place your order, mention you saw this ad and take
an
> additional 5 percent off
> > any weather station price.
> > _______________________________________________
> > Towertalk mailing list
> > Towertalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
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