To avoid these ads, REGISTER NOW!

Driving Ground Rod into Rocky Soil?

FullRaceMerc

Well-known member
Joined
Jan 9, 2015
Messages
3,869
Location
SoCal (SGV)
Any tricks for driving ground rod into very rocky soil? Like former river bed type rocky soil. Big rocks, little rocks, & in between rocks.

I've got a Hitachi SDS Max hammer with a ground rod cup that is just being laughed at by this earth.
 
To avoid these ads, REGISTER NOW!

ctfjr

Well-known member
Joined
Oct 30, 2011
Messages
167
Location
Basketball Capitol of the World
We live on a glacial till - when the glacier receded it dropped all kinds of potatoes & gravel. The drainage is great but not so wonderful for digging or driving in ground rods. For my ham radio station I drove in several with the 'armstrong' method, not so much fun but I was able to get most of them down all the way. The ones that were just too tough to get in all the way - as long as they were down at least six feet - I dug a little recess on top of the ground around the rod, like a moat. I filled it with a couple of pounds of copper sulfate and then gently watered it until it all dissolved & seeped into the ground. Seems to have worked well for me but don't what the reason for your ground rods are.
 

Chukster

Well-known member
Joined
Jan 25, 2012
Messages
2,598
Location
Cary, NC
Electric jackhammer is the bomb for driving ground rods. Can even get a socket just for driving ground rods. Normal soil it's like a hot knife thru butter. Rocky soil, it might be like a cold knife thru cold butter, but that's still better than the armstrong method.

Might be able to do it with a large hammer drill and appropriate socket. Just have plenty of help, esp. during the start; you'll probably have to start from the top of a ladder.
 

airrj

Well-known member
Joined
Apr 4, 2008
Messages
137
Location
Wide Wonderful Wyoming
More of the same from me. We are on decomposed granite, so once you get 12"-18" down there is little to no chance to get the rod in more. So we ended up (per our code official) putting in 4 ground rods at our service. Two were as deep as we could get vertically, about 32" on one, about 36" on the other and then the last 2 were at an extreme angle, so that they are in the topsoil. All connected together.

On our house, when we built, we installed a UFER ground.

And on my Ham radio tower I have 2 driven into the topsoil at a very shallow angle.

Good Luck.
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
20,067
Location
Modesto, CA
More of the same from me. We are on decomposed granite, so once you get 12"-18" down there is little to no chance to get the rod in more. So we ended up (per our code official) putting in 4 ground rods at our service. Two were as deep as we could get vertically, about 32" on one, about 36" on the other and then the last 2 were at an extreme angle, so that they are in the topsoil. All connected together.

On our house, when we built, we installed a UFER ground.

And on my Ham radio tower I have 2 driven into the topsoil at a very shallow angle.

Good Luck.

if u have a UFER ground thrn u dont need rods...
 
To avoid these ads, REGISTER NOW!

dutchgray

Well-known member
Joined
Sep 28, 2014
Messages
6,469
Location
Dorset. England.
If its really rocky ground you could get the longest SDS bit you can get hold of and drill as deep as you can with it, then beat the rod in.
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
20,067
Location
Modesto, CA
The rods are at the meter which is on the barn, which was existing so I couldn't add the UFER. The UFER is on the house which I built, so we added it during construction. Two different structures in two different locations.

aww ok that makes sense now
 
OP
F

FullRaceMerc

Well-known member
Joined
Jan 9, 2015
Messages
3,869
Location
SoCal (SGV)
Thanks for the suggestions. I should have mentioned that UFER isn't an option at this location. Already have the socket for the electric hammer & this soil is laughing at it. Will give the long SDS Max bit a shot. At least it will have a 3' head start. Will probably end up bending it through the ditch once it stops.
 

rockwithjason

Well-known member
Joined
Jan 8, 2006
Messages
2,633
Location
Las Vegas
if you have a home depot near you with a rental yard then rent the electric demolition hammer and the rod driver attachment. usually they have a cabinet with drawers near the desk that has all of the bits in it. you may have to look for the bit there. if you can't drive it with that then you need to trench. be warned that you may run into inspectoritis on this as inspectors can get all kinds of twitchy about this. if you do the trench go to the supply house and get a 10ft rod and bend the last 2ft at 90 deg so you have a full 8ft linear in the ground.
 

toplessHO

Well-known member
Joined
Oct 20, 2014
Messages
14,081
Location
central florida
Ive used both 45 and 90# Pneumatic hammers with attachment to drive rods thru
the rock bed on east coast. We are talking 100ft here.
 
To avoid these ads, REGISTER NOW!
Top Bottom