In a message dated 4/16/03 7:58:49 PM Eastern Daylight Time,
clewis@knology.net writes:
> Depending on the angle
> of the guys, these forces can be huge, often exceeding the vertical
strength
> of the tower. On the other hand, towers intended for guying are designed
for
> high vertical and very low lateral/bending loads.
That is nonsense!
If the guy wires can hold the load, the tower will be stressed less than if
self-supporting. When you have self supporting tower, one side gets stressed
on "pull" while the other side is stressed on "push," the angles are steep
(legs) the forces are large. If you put the guy wire you are freeing the legs
from "pull" and they share the load on "push" which is shared and less. Self
supporting towers are usually heavier material and stronger than guyed
towers. No way you can exceed vertical strength of the tower. Guy wires on
such tower do not need to be tightened, some slack might be beneficial,
allowing tower to do its job, and in case of excessive forces and bending,
the guy wire will help. It is helpful to have the guy wire hanging down
normally and in case of severe ice and wind load, hook it up to the anchor on
the windy side.
This is helpful especially when using rotatable towers (Big Bertha) heavily
loaded with stacked arrays, where in windy situation system might get
"excited" and start swaying. Guy would dampen the oscillations and help to
carry the load. (Yea, Bertha will take big arrays, but there are always some
who will push the envelope :-)
Yuri, K3BU
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