Clay fill for pole barn build

[Jm976711]

Hi all,

I’m looking for some clarification on site preparation for my 24x28 build. The right side (reference to pictures) slopes off and puts me around 2’ off grade. The contractor is proposing that the topsoils be cleared off and then the area that needs to come up to grade be filled in with clay.

Is this a commonly used practice for pole barn builds? I thought it wasn’t ideal to build on top clay. We are using permacolumns and will be adding a French drain around the building to help direct water flow away from the building


Sent from my iPhone using Garage Journal

 

[DevinJ]

Hello,

Clay is a fine material for fill. 2' of fill really isn't that much. Just make sure he compacts each lift (usually every 6 inches). Just make sure you don't have bentonite clay in your area as it an expansive clay and will move around when wet.

You'll probably need about a 100 cubic yards of fill imported (including sloping to existing grades).

I'm in the mass excavation business so if you have any more questions feel free to ask.

Edit: What area of Ohio are you in. I may be able to tell you what soils are in your area.

 

[Jm976711]

Hello,

Clay is a fine material for fill. 2' of fill really isn't that much. Just make sure he compacts each lift (usually every 6 inches). Just make sure you don't have bentonite clay in your area as it an expansive clay and will move around when wet.

You'll probably need about a 100 cubic yards of fill imported (including sloping to existing grades).

I'm in the mass excavation business so if you have any more questions feel free to ask.

Edit: What area of Ohio are you in. I may be able to tell you what soils are in your area.

I was just about to add that information. I’m located in central Ohio in Knox County.


Sent from my iPhone using Garage Journal

 

[DevinJ]

I was just about to add that information. I’m located in central Ohio in Knox County.


Sent from my iPhone using Garage Journal

Ok. I can check at work tomorrow and see if we have any geo tech reports from that area. We may not as most of our work is in Northern Ohio. I'll let you know.

 

[beatuptruck]

I built up my pole barn pad with clay fill harvested from a borrow pit on my property. The site was fairly level (within 18 inches). Although there was about 48" of topsoil that had to be removed and replaced. I figure it took about 120-140 tandem dump truck loads to fill back up the pad.
My builder said fill was fine as long as the bottom of the posts were sitting on virgin soil.

 

[kj_mustang]

My pole barn pad site sloped pretty heavily. It has about 4 feet of fill at the lowest corner. It was filled with clay dug from my new home basement excavation. They used every bit of the dirt dug out for my pad. The pad was packed very well and I have had no issues with the barn and concrete floors in the 6 years since built.

 

[DevinJ]

I just had a look at work, and I don't have any soils borings down by you. Sorry.

You should be just fine importing some clay. Make sure your contractor is bringing in CLEAN fill. There should be very little tree roots, leaves, grass, bricks, etc. All those will decompose overtime and cause settling issues.

 

[Justind97]

Do not fill with clay. Spend the extra few bucks and backfill with clear stone.

If you have clay, you will want to remediate the soil. Spread lime, 50lb bag per 100sqft. Then add 3/4 clear and pack that into the clay. You're attempting to bring the ratio of fines to large stone to 30% or better (larger stones).

Then add Greenline geotextile and then backfill with clear.

You want that base under the pole bar to be as predictable as possible during freeze/thaw cycles. Using clear allows the water to pass through the base quickly.

 

[DevinJ]

Do not fill with clay. Spend the extra few bucks and backfill with clear stone.

If you have clay, you will want to remediate the soil. Spread lime, 50lb bag per 100sqft. Then add 3/4 clear and pack that into the clay. You're attempting to bring the ratio of fines to large stone to 30% or better (larger stones).

Then add Greenline geotextile and then backfill with clear.

You want that base under the pole bar to be as predictable as possible during freeze/thaw cycles. Using clear allows the water to pass through the base quickly.

All of that is not necessary. The geotextile fabric would be a good idea though. He siad he will be putting in french drains, so I don't think draingage will be a problem.

 

[wayout]

From my actual experience, you will have issues with freeze/thaw cycles.
There are no voids in it like stone has.
This allows the moisture that is in it to heave during a freeze cycle.
You can not keep clay from picking up and holding moisture from its environment either. This can lead to rusting and rotting of interior items.

 

[DevinJ]

If you could have your contractor place it and compact it then let it sit for a while and get some freeze and thaw cycles that would probably be the best way to do it. That should let any settling that it's going to do to occur.

 

[Jm976711]

If you could have your contractor place it and compact it then let it sit for a while and get some freeze and thaw cycles that would probably be the best way to do it. That should let any settling that it's going to do to occur.

That currently is the plan. He’s clearing my area Saturday and then getting the clay fill from his farm. My pole barn builder won’t be able to get to my project for another month. So I’m hoping that gives it enough time to settle


Sent from my iPhone using Garage Journal

 

[Justind97]

All of that is not necessary. The geotextile fabric would be a good idea though. He siad he will be putting in french drains, so I don't think draingage will be a problem.

Of course it is. A french drain is not a sponge. It will take any excess water that's in the soil that's makes it's way to the drain, but that's it. Water WILL make its way in there.

This is landscape 101 with many years and use cases behind it from ICPI, International Concrete Paver Institute. The same rule applies except he's likely putting a huge slab on top.

From pictures, this shop will be built downhill of other land. It will have water in the soil.

 

[Jm976711]

Of course it is. A french drain is not a sponge. It will take any excess water that's in the soil that's makes it's way to the drain, but that's it. Water WILL make its way in there.



This is landscape 101 with many years and use cases behind it from ICPI, International Concrete Paver Institute. The same rule applies except he's likely putting a huge slab on top.



From pictures, this shop will be built downhill of other land. It will have water in the soil.

You are correct in that the shop will be built downhill from our house. We will have around 15-20’ between the structures. The water run off is my worry with the clay. We are directing the gutters around the shop and putting in the drains in hopes to offset it.


Sent from my iPhone using Garage Journal

 

[DevinJ]

Of course it is. A french drain is not a sponge. It will take any excess water that's in the soil that's makes it's way to the drain, but that's it. Water WILL make its way in there.

This is landscape 101 with many years and use cases behind it from ICPI, International Concrete Paver Institute. The same rule applies except he's likely putting a huge slab on top.

From pictures, this shop will be built downhill of other land. It will have water in the soil.

Clay is used to line retention ponds all the time, it doesn't absorb water quickly at all. Although once it is absorbed, it will hold it for a while.

If proper drainage is put in the clay will not absorb that much water.

Importing 200 tons of stone is simply not necessary in this case. The only way I could see that is if the soil was absolute garbage, which does not seem to be the case.

 

[ER70S-2]

As someone who used to inspect structure fill placement all the time, there is nothing wrong with clay or any soil type for that matter. It just needs to be the correct moisture content and be compacted correctly. You also need to strip the existing topsoil and confirm that the base is firm and stable before placing the fill. It's not rocket science, but you need someone who knows soil and compaction to have it done successfully.

 

[ER70S-2]

If you could have your contractor place it and compact it then let it sit for a while and get some freeze and thaw cycles that would probably be the best way to do it. That should let any settling that it's going to do to occur.

Sorry, but this is 100% false. All that freeze/thaw is going to do is make it less compacted! Place the fill and compact it properly. That is all you need to do.

 

[DevinJ]

Sorry, but this is 100% false. All that freeze/thaw is going to do is make it less compacted! Place the fill and compact it properly. That is all you need to do.

Correct. I should have worded that differently. I should have said let it sit and let it do any settling its gonna do, recompact it and then build the barn.

If he really is worried about it he shouldn't be asking some random people on a forum, he should contact a geotechnical engineer and get a professional recommendation.

 

[ER70S-2]

Correct. I should have worded that differently. I should have said let it sit and let it do any settling its gonna do, recompact it and then build the barn.

If he really is worried about it he shouldn't be asking some random people on a forum, he should contact a geotechnical engineer and get a professional recommendation.

I used to work for a geotechnical engineering firm and I completely agree with talking to a geotechnical engineer.

If compacted properly, though, no additional settling should occur.

 

[DevinJ]

OP if you really are worried and want a professional recommendation contact PSI or ATC Geotechnical services. They both are nationwide companies, and they both also have branches in Columbus near you.

They'll come out and look at you situation and give you a recommendation on how to proceed.

Realistically if compacted properly and the clay doesn't have a bunch of organics you'll be fine.

 

[Jm976711]

OP if you really are worried and want a professional recommendation contact PSI or ATC Geotechnical services. They both are nationwide companies, and they both also have branches in Columbus near you.

They'll come out and look at you situation and give you a recommendation on how to proceed.

Realistically if compacted properly and the clay doesn't have a bunch of organics you'll be fine.

That’s probably what I should have done, but as you and others have stated, if compacted properly I shouldn’t worry. He used clean clay and spent the day compacting 4-6” at a time with his heavy dump truck loaded with rock.





Sent from my iPhone using Garage Journal

 

[Jm976711]

We have the gutters directing flow away from the clay and also a French drain and culvert drain from the hillside road. I’m hoping this is enough!

We are using permacolumns and laminated posts


Sent from my iPhone using Garage Journal