Pavillion/Garage on pad on top of rock and clay

[boogerman2000]

Hello,
I'm at my wits end. My property is 95% rock/boulders and 5% hard clay. I had an excavator level an area for a 30 X 40 pavillion/garage. I'm going to close half of it in for the garage eventually. I started to try to dig a hole with my Bh80X and after about 6 inches hit solid boulder. I'm going to put the 6 X 6 poles 10feet apart on the long sides and 2 poles each on the short side. This project is going nowhere fast as I don't have a clue how I will be able to get the 6 x 6's into the ground.

Is it possible to make a frame out of 2 X 8's or 2 X 10's and fill with about 4 inches of gravel and have a pad poured and then use 6 x 6 pedastool anchors to set the 6 X 6's on top of the pad? Will it be ok?

I'm truly losing my mind as I have the material sitting in my yard and I can't get the project going.

Please help!

 

[Duffster]

Absolutely!!!

My prefered way to build post frame buildings is on a floating slab.

Only the edge should be 12'' thick and can sit on the dirt and fill the middle with gravel to acheive the desired thickness for the rest of the slab.

 

[boogerman2000]

What do you use for the form to get the 12inches around the edge?

 

[Duffster]

Just a 2 x 12

Or any combo of whatever you got.

 

[carpenter383]

If you're gonna set the posts on top of a floating slab I would add some extra bracing than you'd normally need with the posts in the ground. Also what about using a jackhammer to get the posts down to where you need them? You could pour the floating slab and just stick frame off of it instead of using posts.

 

[boogerman2000]

I actually got about 5 or 6 of the holes down to about 1.5 to 2 feet. I going to try to plumb those posts and cement them in, then run the banding around them and pour the entire floorn ten foot sections.

I thought of a jackhammer but I think I'd just frustrate myself more not to mention beat the **** out of myself.

 

[tommu56]

I actually got about 5 or 6 of the holes down to about 1.5 to 2 feet. I going to try to plumb those posts and cement them in, then run the banding around them and pour the entire floorn ten foot sections.

I thought of a jackhammer but I think I'd just frustrate myself more not to mention beat the **** out of myself.

What kind of rock is it?

Rent a core drill and 8" diameter bit and brake the core out if you have only a couple holes.

The guys that drilled for my pole building used an auger on a skid loader and said they didn't have a problem in my slate/shale with a little dirt.

You want them to be below the frost line and that depends were you are in the state.

tom

 

[boogerman2000]

It's either limestone or sandstone or a mix.

 

[carpenter383]

It may cost a few $ but you could hire someone with a hoe-ram to hammer the holes out.

 

[PA hayseed]

if your in west central PA then your frost line is 3', unless we get a winter like last one. I think the frost line went to about 40-42". That 0 degree and sub zero moved my pole building post. First time it moved, and it didn't move much.

If your 100% sure that your on solid rock, a pad on top won't hurt a thing. Like someone else said, stick frame it from there. If your dead set on sinking those posts, go down till it's solid and do em there. My buddy had the same issue with solid rock for his deck. We dug down to the solid rock, cleared it of muck/dirt, and poured on top of it. If it is solid and big, frost heave won't move it because it's below the frost line.

good luck. Of course you can always hire a drill rig crew with rock coring equipment, but it ain't cheap. You could also use the methods listed in this forum for breaking that rock up, I can't remember the name of the stuff, but the pics on here showed a massive boulder being split up nicely.

here is one of the threads 3rrl posted this, but there are others on this site too.
http://www.tractorbynet.com/forums/rural-living/123658-bustin-up-boulders.html