From: "John WA2GO" <email@example.com>
Subject: [TowerTalk] Tower "DROP ZONE" or "DROP RADIUS" for Rohn 25G &
Content-Type: text/plain; format=flowed
> The Building Inspector is requiring my engineering drawings to specify what
he is calling the "drop zone" or "drop radius" of the tower. >He wants to
see what is the radius of the circle it will all land inside when it all
comes crashing down. (perish the thought!)
> I couldn't find this figure in the Rohn catalog anywhere. The one engineer I
talked to didn't seem to know about it either.
For the self-supporters just use their length; i.e. falling like a tree. It's
not entirely accurate since most towers fail up the tower and generally not at
the base but he just wants to know the fall radius.
For guyed towers they generally fall in circle approximately 1/3 of their
height. There is a study cirulating that documents a bunch of guyed commercial
tower failures and adds creedence to this. The reason they don't fall in a
larger circle is because they're constrained by the remaining guy wires and
fall in a big heap. I've got a copy of the study if you're interested. (I can't
remember the guy's name that did it.)
TOWER TECH -
Professional tower services for commercial and amateur
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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