> When you translate the plane triangle section in rotation in its
plane,
> twist or torque load, initally the guys cannot resist the lateral
> displacement as the guy's line of action is perpendicular to theaction
> direction of the load. As the triangular section twists additionally
then
> there is created an angle between the line of force and the guy line
of
> action which can develop a vector resistance to the movement of the
> triangular section. This value of resistance is a function of the sine
of
> the angle created. It wil start at 0 degrees at rest, sine of 0
degrees
> is 0.
>
> This explains why the torsional resistance of the standard guying
scheme
> is so low and why if significant torsional forces are present in a
tower
> they twist.
>
> In this case the farther away from the center the guy attachment point
is
> really doesn't help with the torsional strength the angle between the
guy
> and the line of force of the torque is what matters.
>
but the farther away the attachment point is from the center of rotation
the bigger the angle on the guy wire so the higher the resistance to the
twist. Granted at 0 there is no force so it won't help with very small
movements but adding rigidly clamped arms that approximately double the
radius of rotation should increase the resistance proportionally. Also
increasing the radius to where the reaction force is applied increases
the length of the arm applying the force also increasing the reaction
torque applied by the guy wires.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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