I also think it is impossible for a guyed tower to "pull apart".. The
harder the wind blows the more downforce is created by the guys. A
tower can fail in compression load as well as bending so the PE analysis
considers both in the design.
Grant KZ1W
On 12/5/2018 10:09 AM, john@kk9a.com wrote:
I am not a PE but to me pulling the tower apart seems very unlikely. If
you use a six way star bracket or Rohn 25-55 guy bracket the outward force
is all on the bracket. Standard Rohn 65G brackets are mounted on each leg
but the tower is quite strong and there is less guy tension with the
shallower angle.
FWIW, whenever possible I also use more guy distance than 80% to allow for
beams to rotate. Also heavier tower allows for less guys which leaves more
room for antennas. Sometimes options are limited, my Aruba house had a
small lot and the guys were close to 50% spacing.
John KK9A
K4XS Wrote:
I too, have gone greater than 80% to allow the antennas on the rotating
tower to clear the guy wires. Currently the top guys on my tower are at
84 feet and are pulled out to around 100 feet. Realize though, that the
tower is now pulling more sideways and less downward than before when it
was at 84 feet. I believe that taken to extremes this would eventually
allow the tower to pull apart in heavy wind, especially if it was Rohn 25.
I have done the height equals guying distance on 200 footers and have had
no issues. However, they were never tested in a hurricane, so who knows?
Bill KH7XS/K4XS
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