Hi all,
I think we're spending energy trying to find a definitive right or wrong answer
when I don't think such a beast exists.
I'd be very leery of guying a freestanding aluminum tower for the
column-buckling reasons outlined in K1TTT's cardboard tube analysis. I would
venture to say these towers have flexibility built in for the same reason
skyscrapers sway.
I would guy a Delhi in a heartbeat (and by extension, Rohn BX, since they are
identical, except for the swagged Rohn look vs. the Delhi taper). That Delhi
specifies guying only bolsters my confidence. (Guying assumes for a moment that
I'm exceeding either the freestanding height or load.) I doubt I'd guy just for
the sake of guying.
I would hazard a guess, however, that the question is academic for other types
(AN, Trylon,etc.) since anyone who is going to exceed the loads on those towers
is likely already looking at something else (45, 55, etc.) as a guyed tower
anyway.
I don't see the point of guying unless you're going to exceed the freestanding
loads, anyway. If so, then why buy a freestander in the first place?
Sure, if you're in a 100-mph zone and your tower is rated for 80, yes, then
there's a point.
But I also think that I wouldn't limit myself to a top set of guys only.
Depending on the height, I'd want to use two sets of guys at least, to prevent
K1TTT's cardboard tube implosion.
And at that point, I'd only want to guy it properly anyway. I don't see the
point of a loosely-tensioned guy just as a failsafe. I doubt that would do much
good anyway. I'd guess that by the time the tower is moving enough that it's
straining the guy wire, it's too late.
Of course, all of this assumes a risk analysis in my favour. If I was planting
this tower in a dense neighbourhood, I'd probably calculate my risk analysis
differently than if this were in the outback (If a tower falls in a forest...)
73, kelly
ve4xt
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