breaking large rock

crazymike

LawnSite Senior Member
Location
Ontario
Hey, I'm revamping the water front at my grandparents cottage for them.

There is a cluster of some very large rocks separating two parts of a beach. These rocks are sharp and very much in the way. They are about 3' x 5' - 6' and who knows how deep they go. It's a black hard rock, some form of granite I believe. It has sharp grooves in it from water/ice action.

This is a family pro bono job that I would like to do as cheap and quick as possible, all while respecting the environment more so than appease the environmentalists.

Because of the size, removing them in one piece is not an option. A full size excavator would struggle even rolling these out of the way.

I'm considering two options. I was going to use a chemical expansion agent to crack the rock and remove the bits. This has to be done in warm weather and I'm not sure how will it work. I have a rotary hammer and wouldn't need to rent any equipment, just buy chemicals. Then use my mini excavator to pick out the broken pieces. Never used this on anything but concrete and won't work on the rocks in the water.

My other option was to rent a breaker for my skidsteer or excavator. Both are standard flow though. I've never used a concrete breaker on a machine and not even sure if this will work on hard rock. I'm just looking to take off the top 3' or so of rock and cover with sand.

I'm trying to find out exact type of rock, but I know I can drill it no problem with a rotary hammer.

cliff notes
- removing some large granite? on water front, About 30 sq ft on surface, who knows how deep
- chemical split or rock breaker for skidsteer/excavator
- want to do it quick and leaning towards the breaker because I can do it in the winter time when I'm slow.

Experience? Thoughts? Other ideas?

blasting is not an option. I don't have a license and don't have the money and it's too small/trivial job to bother with that.

Thanks
 
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crazymike

LawnSite Senior Member
Location
Ontario
Russell thanks, but they are too big. I would have to bring in a full size machine to even budge these rocks. Plus, my luck they would go down too deep. Thanks though.
 

DVS Hardscaper

LawnSite Fanatic
Location
County Jail
This is a no brainer.

Use a breaker on a mid size excavator.

Seldom do we use a breaker on the skid steers. An excavator is much faster, sit in one place and hammer away.


No need for chemicals, voo-doo, or whispering in the rock's ear.

Or you can bring in some horses and connect some ropes to the horses and rocks and have the horses pull the rocks out.

And if none of dat works for you then get a hammer and chissel!

And of discussion.

Topic closed.

Konetzny 3.jpg
 
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crazymike

LawnSite Senior Member
Location
Ontario
alright, thanks. I just didn't know if the breaker could handle granite.

I have to look up flow rates because my excavator is low. It runs my auger fine but not sure if it will handle a breaker.

also, the chemical I was going to use it called dexpan. Drill holes, insert chemical, wait a while and it cracks the rock into manageable pieces.
 

STL Ponds and Waterfalls

LawnSite Bronze Member
Location
St.louis MO
alright, thanks. I just didn't know if the breaker could handle granite.

I have to look up flow rates because my excavator is low. It runs my auger fine but not sure if it will handle a breaker.

also, the chemical I was going to use it called dexpan. Drill holes, insert chemical, wait a while and it cracks the rock into manageable pieces.
Excavators around here have to use dex every once in awhile to keep things moving (machine wise) and usually if the rocks are too big. Problem is the stuff is pretty expensive.
 

joes169

LawnSite Member
Location
WI
Excavators around here have to use dex every once in awhile to keep things moving (machine wise) and usually if the rocks are too big. Problem is the stuff is pretty expensive.
You're right, it's not cheap, but neither is renting a mini-ex and breaker (assuming his won't run a breaker), much less the labor paid out to run the machine & breaker, wear & tear in the machine if he does use his, etc...

Dexpan "can" work extremely well and efficiently, as long as the directions are followed to a tee............
 

SVA_Concrete

LawnSite Senior Member
feathers and wedges (spelling?)

drill holes and drive wedges. pop it apart.
 
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crazymike

LawnSite Senior Member
Location
Ontario
What about dex type 3, the winter one?

I have to look into it. It says it's good down to -5c. But I'm not sure if this is ambient temp or rock temp.

I can get a box for $100 (50lbs) off amazon

I have my doubts my machine will run a breaker efficiently which means I should rent one for the skid. Either way, it's minimum $250 in rental fees for the breaker. So if the dexpan will work, I'm ahead of the game and no rentals needed.

And it's easier on my machine
 

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