Pouring concrete under water

[MossRoad]

If it is a just duck bird house, why even the concrete?

What kind of ducks, by the way? I have a few acres in duck ponds.

OP said wood d-U-c-k-s.

 

[TomSeller]

OP said wood d-U-c-k-s.

Oops. Gotta watch that auto spellcheck feature. I see that now and corrected it.

 

[MossRoad]

Hey, it wasn't misspelled. :laughing:

I corrected my quote, too.

 

[woodlandfarms]

So might I ask how you are digging your post hole?

 

[MossRoad]

I think the OP said he dug the hole and then got 3" of rain, which filled the hole.

 

[Tul01]

I had a similar problem one time, came up with the idea to use a shop vac to suck the water out, worked quite well, cleaned out the bottom too, making the holes back to their true depth. It ended up too slow for the number of holes I was doing so the second half I just poured the concrete in. It seemed to work and push the water out. I have no idea of the long term strength of either they were piles under a concrete ramp/walk up to our front door. Nothing shifted before we moved anyway. I have used to shop vac technique a few times now to clean out the debris at the bottom of the hole to get a few extra inches of depth when putting in posts (we have a fairly deep frost line here approx 5-6' to be safe.)

 

[jix]

Concrete under water is not a problem, but yes excessive water in the mix will result in a degree of weakening of the strength of the concrete. Adding additional Portland cement into the mix will alleviate that. about 20% increase of cement is fine to get 5000 lb mix, despite water in the hole. Rebar will corrode and the rust will, over time, destroy the column of concrete. Addding pozzolan (fly ash) to the mix will slow that process, but will not stop it. I would not put rebar in the column for this reason, but I would consider adding glass fibre to the mix. I would also use crushed rock and not pebbles..

 

[GPintheMitten]

For crying out loud, it's a fence post with a duck box on it.

 

[jix]

I agree.. enuff with this thread

 

[MossRoad]

For crying out loud, it's a fence post with a duck box on it.

Maybe they are fat ducks?