What else that can be done is to drive 1-3 x 8 foot cu rods into the
ground..at the bottom of the hole,
before you pour the concrete. Then cadweld each one...then a short piece of
bare 2 ga stranded Cu wire
from the top of each ground rod to base of tower. Then the 1-3 rods are 8
ft below the bottom of the
concrete, which puts them well below the frost line. I did that on my L+R
tower back in the mid 80’s.
It was 33 inchs across the face, with 20.7 ft long straight sections. All
angle steel, all bolted construction.
Hole was 6x6x6 square, with re-bar. Any lightning passes right down the
tower, right to bottom of the 6 ft deep
block of cement...and continues on another 8 ft down, via the 3 x rods.
Bottom of each rod is then 14 ft below
ground. We used an electric jack hammer, with a special end on it, designed
to drive ground rods. I lost 6 ft
of the 1st 20.7 ft section by placing the tower section into the deep hole.
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