----- Original Message -----
From: <Tower2sell@aol.com>
To: <towertalk@contesting.com>
Sent: Tuesday, October 26, 2004 7:16 PM
Subject: [TowerTalk] Guy Anchor Corrosion Question 1
> Question 1, Part A: Do you know of any towers that
have collapsed because of
> corroded anchors?
In about 1995, mine came close. It was only a 50
footer, with 4-way guying at two levels, using Rohn
screw-in anchors. As a cold front approached, with the
wind picking up, I noticed one of the guys flapping
more than normal in the breeze. I went out to inspect
them, and found two of the opposing guys loose. I
partially tightened one, and went to tighten the other.
As I started turning the turnbuckle on the second one,
I found that instead of tightening the guy, I was
jacking the guy anchor shaft out of the ground!
Fortunately, there was a farm supply store nearby, and
I was able to purchase and install another temporary
screw-in anchor before the wind really started to blow
hard. I later replaced all four anchors with new Rohn
screw-ins.
Inspecting the failed anchor later, I found that the
shaft had totally corroded through, with the corroded
end coming to a pointed shape. The soil here is a top
layer of clay, then a six inch layer of what the locals
call "Caliche," and then a deep (at least six feet
deep) layer of sand. The water level is at six feet.
The rod failed at the point where it passed through the
Caliche layer.
Dave Hachadorian, K6LL
Yuma, AZ
.
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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