# How do you pour concrete in water?



## jogr (Jul 24, 2007)

Can you pump the water out right before you pour the concrete in?


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## jlhaslip (Dec 31, 2009)

What if you place a 6 ft square of 6 mil Poly over the hole and poured the concrete into the middle of it?


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## Gary in WA (Mar 11, 2009)

You mix it first, then dump it in.

Gary


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## jklingel (Dec 21, 2008)

Mell: I don't think Gary is kidding. I assume you are talking about a little bit of surface water, not a deep lake??? I do not think it hurts concrete at all to be dumped into a little bit of water in a deal like this. The edges will get ruined, but if you pour a bit large, it should be fine. Concrete loves to have water added as it dries. For stink and giggles, it would be best if you made some kind of box to hold the 'crete in so it does not become an amorphous blob. If I am reading your situation correctly. j


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## stadry (Jun 20, 2009)

concrete's ' strong ' because of a low water/cement ratio, more cement, rebar, etc,,, 1st, can you dewater the hole be digging connecting holes around it ? this would allow the water in YOUR hole to flow to the hole(s) being pumped out,,, because of the hi wtr, consider spread footings & mix a DRY mix.

another thing is to wait for dick to get up this am :laughing: other'n those suggestions, the others are also good,,, probably never wouldda thought of the plastic - neat ! consider adding some 2' #4 bar from any apron store.


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## Tscarborough (Mar 31, 2006)

Use a treemie or something similar to place the concrete, with the idea being to displace the water, without getting it mixed in with the concrete. Mix it a tad dry, too.

I have placed concrete in 20' drilled and belled piers that were half full of water with no problems.


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## jomama45 (Nov 13, 2008)

I'm assuming you don't want the dirty, mixed water all over the basement floor. So, here's my suggestion: Bucket out as much water as possible, getting it under an ich is ideal. Pour one "sacrificial" bag into the hole to suck up the remaining water.

If you try to displace the water instead, make sure you work the water out at a corner, rather than trapping it.


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## Gary in WA (Mar 11, 2009)

Three different times I helped my dad pour concrete for our retaining wall in the lake, three feet deep, into forms filled with water. As the concrete went in the water came out over the form tops. Set up just fine, lasted 20 years, may still be there as place was sold.

Gary


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## jomama45 (Nov 13, 2008)

GBR in WA said:


> Three different times I helped my dad pour concrete for our retaining wall in the lake, three feet deep, into forms filled with water. As the concrete went in the water came out over the form tops. Set up just fine, lasted 20 years, may still be there as place was sold.
> 
> Gary


 
Couldn't have worked that well Gary if you had to pour the same wall 3 times................... :whistling2: j/k

You do have to be careful though with trapping water (or worse yet, sloppy mud) inside the concrete. It just takes a little forsight to accomplish though. Concrete does real well in strength gains as well, it just takes a little longer in the first few days.


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## Gary in WA (Mar 11, 2009)

Whoops! Three different times for the 10' long wall sections poured on three different days. 50 years ago, don't remember all the details, just the hard work when I was 13! lol.

Gary


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## stadry (Jun 20, 2009)

your dad couldn't have picked a better way to cure his conc,,, our test are taken to dot for immersion curing prior to breaks,,, btw, was 13 when 1st introduced to a 90# jackhammer  didn't like it then & still don't 55yrs later :laughing:


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## mrgins (Jan 19, 2009)

more water=weaker concrete and poorer curing. I'd suggest digging the hole deeper, putting in gravel, and maybe lining the hole (before the gravel goes in) with aluminum flashing. The plastic idea is probably a good idea too so it can set without the water weakening it.


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## Gary in WA (Mar 11, 2009)

*Will concrete harden under water?* 
Portland cement is a hydraulic cement which means that it sets and hardens due to a chemical reaction with water. Consequently, it will harden under water. http://www.cement.org/basics/concretebasics_faqs.asp

Then in the 1700's Joseph Aspdin, a British citizen, discovered that if he added clay to limestone then superheated it, the resulting mixture would set anywhere, even under water. He patented what he called _Portland_ cement, which is still the cement in use today. Dams, oilrigs, dock supports, bridges, lighthouses and various other structures are made with Portland cement. http://www.wisegeek.com/what-is-the-difference-between-concrete-and-cement.htm


This is by far the best method of curing as it satisfies all the requirements of curing, namely, promotion of hydration, elimination of shrinkage and absorption of the heat of hydration. It is pointed out that even if the membrane method is adopted, it is desirable that a certain extent of water curing is done before the concrete is covered with membranes. Water curing can be done in the following ways: 
(a) Immersion 
(b) Ponding 
(c) Spraying or Fogging 
(d) Wet covering 
The precast concrete items are normally immersed in curing tanks for a certain duration. Pavement slabs, roof slab etc. are covered under water by making small ponds. Vertical retaining wall or plastered surfaces or concrete columns etc. are cured by spraying water. In some cases, wet coverings such as wet gunny bags, hessian cloth, jute matting, straw etc., are wrapped to vertical surface for keeping the concrete wet. For horizontal surfaces saw dust, earth or sand are used as wet covering to keep the concrete in wet condition for a longer time so that the concrete is not unduly dried to prevent hydration. http://www.aboutcivil.com/curing-of-concrete-types-methods.html


Gary


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## concretemasonry (Oct 10, 2006)

mrgins -

You simplified concept of more water weakens concrete is generally right if it is mixing water. If it is a high cement content, more water is needed for complete curing.

This is just a construction technique and not a mix design.

The goal is to place the concrete without incorporating too much extra water from the surrounding. conditions with a drier than average mix less than 3-4" slump and we willing to accept a very minor amount of of soil and some water contamination at the bottom interface. Generally, the concrete should be introduced near the bottom of the pour and t0 let the concrete rise from below and displace the water out the top of the forms. It is done every day and the resultion concrete is usually far superior to normally placed concrete on a footing or slab because of the moisture available for curing and the proper temperatures.

I would be more concerned with the effects of the water reducing the bearing strength of the soil. Obviously, there is no interior drain tile and a lack of drainage control.

Dick


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## mrgins (Jan 19, 2009)

I stand corrected. Thanks for the info


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