Date: Wed, 19 Jun 2013 12:36:07 -0500
From: "K0DAN" <k0dan@comcast.net>
To: "Pete Smith N4ZR" <n4zr@contesting.com>,
<towertalk@contesting.com>
Subject: Re: [TowerTalk] Guy Anchor Safety was:Re: Screw Anchor
Experience
I am neither an M.E. nor a tower installer, however I worked 30+ years in
the land mobile industry. My understanding is that multiple ground anchors
are required by manufacturer specs (for very tall, or very heavily loaded
towers), and/or for towers with large side-arms, microwave dishes, etc.,
which introduce big twisting forces on the tower. The use of "star braces"
and multiple guy anchors are to accommodate these forces, not so much to
provide redundancy. Some of the guys on this reflector who are in the biz
can probably shed more light on this.
73
de
k0dan
## I worked for the local telco for 34 years and saw the same thing. Then
toss in
severe ice loading + high winds from mountain top sites, and you can see the
problems
involved.
## For a typ ham tower, even if 6 x guy anchors were used, say 3 inner..and 3
outer, ANY
failure of the 6 anchors will still bring the tower down.
## I still would not mess with typ anchor rods, even if the portion in
contact with the dirt is coated
with roofing pitch. 6 to 10 inch OD tubing, embedded in a huge deep block of
concrete, with the
tube filled with concrete is not about to fall apart down the road. Weld a
steel plate to the bottom of the
tube, then add the rocket fins...then get the entire assy galvanized. Add
rebar to the hole of course..and
use 5000 psi concrete, Crown the top of the concrete so water flows away from
the steel tube.
## concrete weighs 4000 lbs per cubic yard, so you do the maths. Screw in
anchors are for telephone
poles, and phone poles are already 6 feet into the ground.
Jim VE7RF
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