Filling sono tubes - buy bags or mix my own concrete?

[newbury]

Doesn't look like a problem in this particular case. The job is 9 separate tubes, each with about 5 cubic feet. Anyway you do it, each tube is only an hour or two of work. As long as you are putting wet concrete against wet concrete, there won't be a problem. Large continuous pours sometimes go for days. If you ever have to pour wet against dry (set up) then you need to make a cold joint and allow for the inevitable cracking at that point.

KennyG nailed it.
Since a couple of TBN'ers have no qualms about the quality of the bags the bags seem a viable option. Since I need < 1 yard total bags from Lowes look like the way to go. And the Lowes is < 1/2 mile if I get bad bags. Local prices for sand and stone look like about $10 cheaper for the entire project, not worth even my retired pay rate.

 

[boggen]

how large are the sono tubes? are we talking 6" or 12" in diameter? 9 tubes all together. just get the bags and be done with it.

the bag was nothing but cement (no sand or aggregate). 20% is not an acceptable failure rate.

cement = the glue. more glue just fine. rock and sand = filler. now if bag was nearly all rock and/or mostly sand, then i would have a very big issue.

since ya working only a couple hours at a time. load up truck / trailer at local hardware store with bags. toss them into shed. and drag a few out at a time as you deal with the holes.

the bags stack fairly nice. so no big trailer with a mess on it setting in garage or like. the bags are for most part protected from some moisture.

 

[4570Man]

i would worry that some of it would be drying and then not form uniformly togeather as it takes so long.

This method is faster than you think. I could dump in more concrete than one guy could spread. When we poured the foundation on the house we used a full sized backhoe which could move concrete about as fast as trying to reposition the truck. Moving concrete with a tractor even if it is a BX is still faster and cheaper than getting the cement truck stuck.

 

[jix]

Small dia sonotubes, use mixes from scratch and vibrate it wet (by using a rod in a hammer drill) use good clean sand and small size crush, easy on the water. 3, 4 , 5 mix to two ot two and a half gallons of water in a mixer. Keep the mix stiff if you want strong concrete. Ditto bigger tubes, if you can mix the concrete swiftly and pour the tubes before it starts to set (two hours) Vibrate it to release trapped air as you pour to avoid air voids. Use fresh porland cement not old stock. If you are using BIGFOOT molds on the bottoms of the sonno tubes,(highly recommended) get it trucked in and pour it stiff with vibration tamping. POZZOLAN fly ash is worth the cost for extra strength and wet soil situations, If you are to load these concrete posts heavily. Always get the posts base down below the frost line (4 feet, minimum in cold places) Be sure that the bigfoot is level or plumb in the hole before you pour. Proper technique is critical for good post foundations. NEVER use them upon a clay base, put plenty of crushed stone in the hole if the ground is clay.. MIN is two feet, more is better, to prevent tipping under load.
jix





Jix