pouring concrete dry

[jerrybob]

Good comments above......you don't want to dry pour unless the boat you are covering is no longer wanted and you have good insurance on it!

 

[etcallhome]

I agree with the others about the retaining wall. but as for the fence post ??? Around here if using pressure treated post for buildings and then just for post Sakrete is saying do not put concrete around a post .. Reason once the concrete sets up it will stay one size, right , well the wooden post is wet ,or has moisture content ,it dries out shrinks, then leaves moisture come in crack between edge of concrete and the wooden post . will cause your post to rot out quicker.
Older brother was told this by a Sakrete rep last fall.

 

[LD1]

I agree with about everything said.

At 25' long, 3' high, and 4" thick, you need 25 cu ft of concrete. Thats 50 bags, and about $150-$200 worth of cement. And will all be wasted if you dont mix it. And a TON of work if you do.

Most concrete outfits have a $300 or so minimum. Well worth the extra money. You may not think so now, but if you opt to hand mix, you will agree with me long before you get 50 bags mixed.

I also agree that there are better ways of doing a retaining wall. I like the stackable blocks personally. Best looking, and much easier.The 12" wide and 5-1/2" high blocks are only $2 each. 6 rows (about 33") for 25' is only 150 block. And will look a whole ton better than a plain concrete wall.

 

[Short Game]

As far as fence posts go, I live where they can hardly dry out. I never set any post in concrete, unless I want to make it so heavy that someone would not want to pull it out by hand and steal it.

A local farmer's kid taught me fence post science. It's all in the tamping. I tamp it, and tamp it hard, every couple of inches of dirt, starting right at the bottom, all the way to the top. I bless that kid every time I set any kind of post in a hole.

 

[/pine]

In my experience just gravel works as good as concrete mix for stetting posts...unless it is a gate post where any stress or strain is not static...IMO setting them in wet mixed concrete is a waste of time and effort...

 

[quicksandfarmer]

Some people build retaining walls from unopened bags:
http://www.tractorbynet.com/forums/photos/95343-retaining-wall-unopened-sacks-concrete.html

 

[whistlepig]

I wouldn't hang a gate on a post that wasn't set in concrete. And I sure wouldn't give a good tug with the tractor stretching a fence against corner brace posts that weren't set in concrete. Concrete may rot the posts out. Some of mine have been in the ground over twenty years now with out rotting.

 

[okclumberjack]

I like the post that quicksandfarmer posted from bird , stacked bags with rebar might be what i do , but i still think it's the same concept as pouring into a form dry, keep it wet for a few days the take your forms apart & have a solid wall i have pulled fence poles out that were poured dry & there isn't any soft crumbly concrete attached to that fence pole it's solid as a granite rock.

 

[bcp]

Build a small test section of form and try it with several bags.

Maybe we will all be surprised.

Bruce

 

[Drexel]

If you compare prices you may find that having a truck come is less expensive than buying pre-mixed bags.

I mixed approximately 133 80# bags of concrete for my pole barn thinking that mixing it myself would be cheaper then having a concrete truck deliver.
Six months later, while building a new home I needed about the same amount of concrete to support a 16x24 ft. deck. Because of the size of the concrete pillers I was afraid I wouldn't be able to mix the concrete fast enough to keep part of it from drying before I was finished so I hired a truck to deliver the concrete.
Even with the extra charge for ordering under a certain amount of concrete I still came out cheaper then if I'd mixed it myself. Oh well, you know what they say about assume.