N4KG response inserted below.
On Tue, 08 Oct 2002 kb9cry@attbi.com writes:
> I am chemical engineer so don't bash me too much but the
> way I understand it, there are horizontal forces acting
> on a tower's base, albeit less than the vertical
> forces. Imagine the tower being blown by the wind, the
> top of the tower will tilt toward the leeward side or
> away from the wind. The bottom will want to kick out if
> it wasn't held fast.
This is valid for a tower with only ONE set of guys where
the guys act as a pivot point. The force at the base will
be reduced by the ratio of the spacing between the guy
and the antenna and the guy and ground (say 3 or 4 to 1).
The tower in question has FOUR sets of guys at 20, 40,
60, and 75 ft. My *assumption* is that there is very little
lateral force left at the BASE. Can anyone PROVE me wrong?
(I don't have a clue how to resolve a 3 load 4 guy system either :-)
Tom N4KG
In high winds the guys will
> stretch, can't prevent it, and the tower will lean.
> This is why commercial folks use tapered bases, so that
> the leaning tower doesn't put undo compressive load
> acting down on the leg away from the wind. Phil KB9CRY
SNIP
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