[TowerTalk] Guying a self-supporting tower - Yes

[David Robbins K1TTT]

> > 2) A more fundamental question would be is there any configuration (i.e.
> > combination of stiffness and strength) where the guyed column would fail
> and
> > the canteliever beam would not, with the same lateral load.  This would
> > answer the "it can't possibly happen question", since all you need is
> one
> > example where a plausible structure will fail with guys but not without.
> 
> This is the question I'm interested in. Because if it turns out that
> it's difficult to design even a ridiculous structure that is weakened
> by guys, some good light will be shed.

I am good at the ridiculous.. 

just use the example of a very weak tube, like a cardboard paper towel tube.
It will stand upright very nicely by itself... but then add a couple of
strong cords pulling down at a steep angle and it will crush even without an
added load of wind.

Or take a piece of balsa or other light wood, put guys to the top of it and
tension to just about the breaking point, then give the wood a bit of a push
in the middle and it will snap... extend the wood above the guys a bit and
give it a push up there and it will pivot around the guy point and break
below the guys the same way.

There are lots of ways to apply guys to something that can't handle the
extra down force that will make it buckle and collapse.





David Robbins K1TTT
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