Concrete base

[JMER817]

So prepping for my future Polebarn I had to cut down and remove a dozen or so trees. Had an excavator come out and rip out the stumps. I sifted thru with my box blade and brought in 100yards of bank run fill dirt. The depth of the fill dirt because of the slope ranges from 6” on one end and up to 30” on the other end. I spread it in 2-3 lifts using my Harley rake. My plan was to let it settle over the winter and let the freeze/thaw cycle do its thing. I figured this would be enough compaction before laying the concrete floor. Now I am beginning to second guess myself. Should I have compacted it in multiple layers with a plate compactor? Debating if I need to strip down and re-level but use the compactor. Thoughts?

 

[Jstpssng]

Frost and rain are the best compactors you will get. By spring it will be fine. Are you going to put down foam board before pouring? Aside from the obvious insulating value it will also spread out the weight of the concrete, although I doubt that you would have a problem anyways. Just make sure that the frost is completely out before you start pouring, it can go down a long ways in gravel.

 

[EddieWalker]

Plate compactors are horrible for compacting soil. They are more for compacting a few inches of base for patio pavers.

I would fill up the front bucket with a load of dirt and drive over the pad so my tires covered ever inch of it multiple times. Then I would do that again a few days after it rains. And depending on how hard the pad gets, I might do it again a month or two later after it rains.

 

[RNeumann]

What is bank run fill dirt? The pics show something with organics and maybe clay?

 

[JMER817]

What is bank run fill dirt? The pics show something with organics and maybe clay?

Mixture of small stones, sand, and a little clay. Everyone around me uses it for fill.

 

[JMER817]

Plate compactors are horrible for compacting soil. They are more for compacting a few inches of base for patio pavers.

I would fill up the front bucket with a load of dirt and drive over the pad so my tires covered ever inch of it multiple times. Then I would do that again a few days after it rains. And depending on how hard the pad gets, I might do it again a month or two later after it rains.

I see that I can rent 450lb plate compactor which states can compact up to 16”. If I decided to rent one this would be this larger unit. Most other compactors are around the 150lb range.

 

[RNeumann]

Mixture of small stones, sand, and a little clay. Everyone around me uses it for fill.

That should lay in fine. The footings for the poles would get into the native soil below. The flat work should be over a few inches of sand- I’d put the sand in right before I did the flat work.

I don’t think the imported soil will benefit from re-laying it in smaller lifts. Sand and small stone don’t get much tighter with added weight and or moisture.

 

[s219]

If you did it in 2-3" lifts and then drove over each layer to compact it, I think you'll be fine. That's what I did for my barn 5 years ago (using a base of #3 gravel with layers of compactable sand/clay fill). Have not seen any settling issues at all.

 

[Egon]

With the amount of granular material your’e fill contains a small smooth drum vibratory would be ideal. The plate compactor also works. Both take a little time. Especially the plate compactor. As the clay content rises toothed compactors work better.

 

[Streetcar]

Definitely get roller or large plate compactor. Material will take years to self compact . Ideally material should be compacted in 6" lifts

 

[EddieWalker]

Plate compactors and smooth drum compactors are for compacting gravel. Vibratory Sheepsfoot Compactors are designed for compacting soil, especially clay. There are different types of clay, dozens of them. The clay that is used for building pads and roads is mixed while it's compacted by the teeth in the sheepsfoot compactor. Water levels in the clay have to be correct. Not enough or too much and you don't accomplish anything. A poor mans substitute for a sheeps foot roller or compactor are the knobs on the front wheels of a tractor. Add a load of dirt to the bucket and you should sink into the fill enough to mix it while compacting it. You just keep going over it again and again until you stop sinking into it. This also works great for filling tree stump holes. Dump a load of dirt into the hole and drive over it, dump another load and drive over it, and so on until you have a slight mound that you no longer sink into.

Considering that you have already built up the pad, the only thing that is going to give you and compaction is something with as much weight as possible, and concentrated on a small an area as possible. Your front tires of your tractor are the best that you are going to get without tearing it apart and doing it again.

When I got out of the Marine Corps back in 88, my first job was running a water truck on construction sites. I sprayed the dirt that was used to build up pads, or fill in ditches or whatever had been dug out. The wheel loader operator would mix the soil as I sprayed it to get the right mixture. He would dump or spread it where it needed to be, and then a sheepsfoot roller would work it while he was getting another load.

When done, the Inspector would put a box over it that sent a beam into the soil to determine what level of compaction was achieved. I forget what was needed to pass, but think it was somewhere in the upper 90% range. Usually they got it on the first attempt, but a few times it had to be dug out and done again. It wasn't possible to get 100% compaction, and the few times it failed, it was off by a point or two. This took a lot of time and effort.

 

[Streetcar]

Eddie
The pad has a lot of granular material in it. For that reason smooth drum roller will work. The guage for density uses radiation. All technicians must wear radiation badges