Giant Rock

[iTom]

Hello. I am clearing some ground for where I want to put in grass in my yard where it was previously all weeds with my Bobcat. Suddenly I came to a hault and my machine got stuck on a rock. Upon closer inspection, this rock is a big momma. It's about 3 feet in diameter and goes down for what seems like forever. Ledge runs through my property and I would not be surprised if that's what it is. I only need to take off enough of the top to put in soil and grass. I tried a hammer and chisel which actually worked for some of the rock but it's too tedious. The other problem is that part of the rock DOES NOT BREAK UP I have tried a jackhammer that bounced off and the rock simply turns to white powder at the top.

Any suggestions?

Thanks!

 

[groundcover]

I had one about the size of a Honda . Had a friend with a Volvo excavator dig a big hole next to it and we burried it. Now I need to do some seeding !

 

[iTom]

That sounds like a pretty big project. My rock sticks out of the ground and is attached to subterranean ledge. I don't think I can bury it without raising the grade of the property, which won't work since the house is already built!:laughing:

 

[rekees4300]

Steps:
1 Use a pointed shovel to dig around the rock to expose its size and shape.
2 Drill a series of 1/2-inch-diameter holes into the rock with an electric rotary hammer.
3 Blow dust from the holes with a bulb-type syringe.
4 Into each hole, drop two feathers and one wedge; be sure the wedges are inserted between the feathers, and that the feathers face out toward the edge of the rock.
5 Lightly tap each wedge with a hammer to tighten it into the hole.
6 Next, use a 3-pound sledgehammer to alternately pound the wedges into the holes; keep hitting the wedges a little at a time until the rock cracks.
7 Pry apart the split rock with a long-handled pry bar.
8 For very large boulders, rent a diesel-powered air compressor and rotary rock hammer.
9 Drill a series of large holes into the rock, then insert the extra-large feathers and wedges.
10 Tap the wedges with a hammer to set them into the holes.
11 Use the pneumatic jackhammer to drive in the wedges and split the rock.
12 Pry off the broken rock pieces with a pry bar.
13 Continue drilling holes and spitting off pieces until the rock is gone.

Source: How to Remove a Boulder | Video | This Old House

 

[/pine]

Google "Dexpan" It works like dynamite without any blast/explosion etc...

 

[groundcover]

Could try something like this : Rock Removal Technologies | Micro-Blaster description, accoessories, and ordering

Could drill a row of holes and split a piece off with 'feathers and wedges' the feathers are thin pieces of metal that small wedges go between. Start at one end and give each wedge a few wacks ,go back and forth till the rock splits off.

If you don't mind the time needed you could drill a few holes and fill with water next winter. Let mother nature freeze it up and the expanding ice will split the rock. Good luck !

 

[quicksandfarmer]

That sounds like a "medium" rock to me! By New England standards, "large" is one you can see from space, "giant" means there's room for the faces of your four favorite presidents...

I think your choices are to either bury it where it lies, dig a hole and roll it in, pull it out, or break it up.

There's some good info here on breaking up rocks:
Hand Drilling and Breaking Rock for Wilderness Trail Maintenance - 84232602 - Forest Service Publications - Publications - Recreational Trails - Environment - FHWA

Also Google Dexpan.

 

[creekbend]

I wish to offer thanks to the Op and all other members for your contributions. I have learned quite alot by reviewing this thread.

 

[TCJatko]

You could get this guy to help: Clint Eastwood vs. Richard Kiel - YouTube

 

[sjb]

I had a piece of ledge approx 4' x 6' near the end of my driveway that was blocking my view of oncoming traffic. It looked like granite, but I don't know a lot about rocks.

The first thing that I tried was drilling some holes and filling with water during the winter. Every time someone asks about a rock, that suggestion seems to come up. It was an absolute waste of time. The winter I tried this we had many night below zero, and at least a week where the daytime temps didn't get out of single digits. The water in the holes froze, but didn't do anything to the rock.

I then bought some feathers and wedges, and tried to split the rock horizontally about a foot from the top. I think had 6 sets of feathers and wedges for 1/2" holes. When driving the wedges all that happened was that the rock would blow out around the holes instead of cracking across. I tried many different combinations of hole locations ( all holes on one face, holes all the way around the rock etc ) without splitting off any large pieces of this rock. After a couple of long days of drilling and hammering, I had managed to break off about a wheelbarrow load of small rock pieces.

I then bought 4 larger sets of feathers and wedges ( these took a 1" hole) and borrowed a larger hammer drill. I again tried to split a foot or so off of the top of the rock. The results weren't much different than with the smaller wedges.

I then bought a bag of Dexpan ( an expanding grout used to fracture rock) , and rented a SDS hammer drill and 1 1/2" bit. I drilled a series of holes straight down in the top of the rock on a roughly 18" grid, around 18" deep ( that was the length of the bit). Mixed up the Dexpan and poured it in.
The next morning I checked and absolutely nothing had happened. At this point I thought that this was yet another failure.

After around three days I noticed some hairline cracks between the holes. After a week or so there were 1/4" wide cracks between all holes and extending down the side of the rock. The sections of rock were also separated from the ledge at around grade level .This was also approximately the bottom of my drill holes. I then use a prybar to knock the pieces over and used the 1/2 feathers and wedges to break the pieces in to liftable chunks.

If I where faced with your rock I would go straight to the Dexpan.


Stan