Little help figuring out how to "bell" my piers.

[Keller]

Hey guys I'm going to be digging or rather "drilling" 18 holes tomorrow.

and I want to "bell" my piers. problem it I don't know how. :laughing:




I have a Bobcat 773g and I will be renting a hydro auger.




How do you guys do it? Do you just use a spade around the hole and clean out with a post hole digger?







My Gpa thinks I can just rock the bit around in the hole and it will kinda woller out the hole like a bell.but I'm scared I will bend the bit. :laughing:

 

[Robert_in_NY]

Just use the post hold digger and carve out the bottom of the hole how you want it. If you try to move the auger while in the hole you will have a wide hole on top and narrow on bottom since the top of the ground will give away much easier then the bottom.

 

[Duffster]

Why do they need to be "belled"?

 

[Keller]

Why do they need to be "belled"?

I'm building a large steel building on these piers.


I was told belling the piers would be much stronger than just a drilled hole.




it's actually is code here as well but since were a farm... no inspections needed.

 

[EddieWalker]

I'm wondering that too? Why not just make the holes bigger?

Eddie

 

[5030]

Around here we call it 'crumbing out' the hole. When you make it belled on the bottom, the concrete around the post becomes a plug and pulling upward on the earth in a plug fashion takes much more resistance than a straight side hole or a tapered hole (which is what happens when you rock the auger in the bore).

One reason we always 'crumb out' the hole with a clamshell post hole digger.

It's code here too.

 

[Keller]

Around here we call it 'crumbing out' the hole. When you make it belled on the bottom, the concrete around the post becomes a plug and pulling upward on the earth in a plug fashion takes much more resistance than a straight side hole or a tapered hole (which is what happens when you rock the auger in the bore).

One reason we always 'crumb out' the hole with a clamshell post hole digger.

It's code here too.

Exactly. It makes it harder to lift. and harder to sink.



except code here is 16' hole with a 36" bell. :confused2:


Now how the **** do you do that.

 

[Keller]

Really? it blanked out He!! :laughing:

 

[BoFuller]

My piers are going to be at least 36 inches deep, probably more. I'm digging about thirty holes that will be 3' X 3' square, then making forms out of plywood that taper the top down to 12" X 18". Three of them will be 4' X 4' at the bottom. Then after taking off the forms, packing the dirt back in. Same end result - keeps the frost from lifting them.

 

[Keller]

My piers are going to be at least 36 inches deep, probably more. I'm digging about thirty holes that will be 3' X 3' square, then making forms out of plywood that taper the top down to 12" X 18". Three of them will be 4' X 4' at the bottom. Then after taking off the forms, packing the dirt back in. Same end result - keeps the frost from lifting them.

At almost a yard of concrete a piece that's flipping nuts.



let alone $$$$$$ :confused2: