Can I incorporate reinforced concrete and a steel building into a radial
field?
About 20% of my 60 buried radials from a grounded tower will encounter
concrete pads/driveway before they get to the "target" length of about
90'. One reference I found quotes moist concrete as having a
resistivity of 10,000 ohm-cm or 0.1mS if my decimal places are correct.
Moist is easy here in Western WA. Since there is rebar in the concrete
on 18" or less centers, the edge to edge resistivity is certainly much
better, so it seems logical to try to extend the radial field somehow
with the existing concrete surfaces (3000 sq ft or so).
My question is what to do at the ends of the radials that terminate at
the concrete. The rebar is not accessible without a jackhammer, so that
alternative is out. I could tie the radial ends to a copper water pipe
or 2" wide copper strap buried along the concrete edge to provide more
surface area and a higher conductivity path, although I am a bit
mystified about whether perimeter wires are a good or bad idea in radial
systems.
About 8 of the 60 radials will encounter a 4000 sq ft steel building at
an average distance of 65' or so, and a Ufer ground is accessible in the
perimeter foundation. Or I can bolt radials to the steel sides. So,
same question.
Since I can't avoid making these conductive surfaces affect the pattern,
it seems I should connect them as best as possible to the radial field
and take advantage of their highly conductive nature ???
I do thank the past responders to my questions. I'm learning a lot.
Grant KZ1W
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Stew Perry Topband Distance Challenge coming on December 29th.
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