On 1/19/16 7:26 AM, David Robbins wrote:
if you really think you need to expend that much effort to get a good ground
start reading with some of this list:
https://www.google.com/?gws_rd=ssl#q=concrete+bentonite+mix+for+grounding
Fascinating..
there's a mention of a conductive cement mix (presumably bentonite and
portland cement and maybe sand?) that you put in dry. It absorbs
moisture from the soil and forms a permanently better conductor. I'm not
sure I completely buy this: for ions to be mobile (and conductive)
there needs to be moisture. I can certainly buy that the cement mixture
will be more conductive than the surrounding soil, and since in a
grounding application, what you're really doing is trying to get a large
surface area conductor, it probably works.
The ecmweb article (a few hits from the top) describes this process:
Placement of ground enhancement material is quick and easy. For
installation around a ground rod (Fig. 4, in original article), auger a
3 in. to 6 in. diameter hole to a depth equal to 6 in. less than the rod
length. Drop the rod down the hole with the lower end centered and
driven into the earth at least 12 in. Make the connection of the
grounding conductor to the ground rod. Then, fill most of the hole using
ground enhancement material.
The installation of a conductor in a trench involves six steps as listed
below. Refer to Fig. 5, for more guidance. Should you use a
conductive-type cement for ground enhancement, see the estimated amount
of linear feet obtainable from a bag of material for use as ground
conductor covering in Table 2 (on page 64P, in original article).
Dig a trench at least 4 in. wide by 30 in. deep, or below the frost
line, whichever is deeper.
Spread out enough ground enhancement material (either dry or in a
slurry) to cover the bottom of the trench, about 1 in. deep.
Place the conductor on top of the ground enhancement material.
Spread more ground enhancement material on top of the conductor to
completely cover the conductor, about l in. deep.
Carefully cover the ground enhancement material with soil to a
depth of about 4 in., making sure not to expose the conductor.
Tamp the soil down, and fill in the trench.
I can't find "the original article" as referenced in the ecm web page..
But I did find this:
https://www.erico.com/category.asp?category=R2387#catalog-documents
or
https://www.erico.com/catalog/literature/E978B-WWEN.pdf
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