Grounding in Shallow Rock

Status
Not open for further replies.
S

sc57ford

Member
Location
South Carolina
We have encountered shallow rock at our building site. The proposed solution is to use a drilled hole and install the Lyncole XIT system, straight shaft. Their system uses Western Bentonite as the backfill material. Any experience with this system and are there other comparable systems out there for consideration.
Thanks for your input.
 
sc57ford said:
We have encountered shallow rock at our building site. The proposed solution is to use a drilled hole and install the Lyncole XIT system, straight shaft. Their system uses Western Bentonite as the backfill material. Any experience with this system and are there other comparable systems out there for consideration.
Thanks for your input.
Click to expand...

the real solution is forget about ground rod(s) and just use the CEE.
 
I agree with the others. Unless engineering specifically calls for ground rods, another more practical electrode would be more suitable for the conditions.

Are you grounding an electrical service or lightning protection system?
 
1. As noted above what do the spec.s require? If the NEC mandated requirement is all that is NEEDED see above.
2. Has four point testing been completed to determine the soil resistivity?
3. Has an engineering firm that can calculate what you need to install in the conditions determined by the test been contacted?
4. In any case the CEE will meet NEC requirements and lower the reisitance of any supplemental Grounding Electrodes that may be required to meet specifications.




http://www.aemc.com/techinfo/appnotes/Ground_Resistance_Testers/App-Ground-SoilResistivity.pdf

http://www.aemc.com/techinfo/techworkbooks/ground_resistance_testers/950-WKBK-GROUND-WEB.pdf
 
I've used the Lincole systems in rock and in limestone. They knocked down the measured resistance considerably. But I believe the reduction was not due to the Lincole rods and salts as much as the increased surface area contact provided by the pipe and the large hole filled with bentonite. The increased diameter compared to the rod accounted for most of the gain.

So why not just use the Ufer ground system you probably already have in the slab, rebar and foundation? That concrete has a lot more area than any rod buried horizontal or vertical.
 
Last edited:
Status
Not open for further replies.
Top