>It seems to me that it would be easier to drill round holes with a tractor
>powered post hole digger for the guy wire anchor points than try and dig
>them by hand. If I use the same amount of concrete as spec'd by Rohn for
>their rectangular anchor, wouldn't I be OK? For anchor "4b" that would be
>.67 yards.
There is more to anchor design than just using the same amount of concrete
that Rohn does. The SHAPE of the concrete piece undergound has a LOT to do
with how much it will hold. It isn't just the concrete that is holding the
guy wires, but also all the dirt on top of the concrete that has to move if
the concrete moves. So what you really want is to have the concrete spread
out somewhat and way down deep so there is lots of dirt on top of it. You
don't want the concrete spread out so much that it is weak and might break,
however. The shape of Rohn's concrete blocks tends to be rectangular and
lying horizontally and quite deep underground. They also use some rebar to
make sure it won't break up.
I, too, noticed there is no numbers given for the dimension "D" which is the
depth of the anchor. I did notice, however, that the diagrams show the top
of the anchor rod just protruding from the ground which suggests to me you
should bury it as deep as possible. Mine are down about 6 feet. I used 9
foot anchor rods so I could have about a foot of rod above ground.
Stan w7ni@teleport.com
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