best tower direction in prevailing wind

[T. A. Russell]

Pat, I believe you have misconstrued each point I made.

I did NOT say the tension in each guy was equal.

Let me re-phrase my comment:

If the wind comes from an angle that exactly bisects two guy wires, 
(perpendicular to a tower FACE), the tension in those TWO guy wires 
is EXACTLY EQUAL to the tension that would result in a SINGLE guy 
wire if the wind were coming in the direction of that single guy wire.

The worst case is when the wind comes IN THE PLANE of a tower
FACE (NOT perpendicular to the face), which is 30 degrees removed
from a guy wire.  This places one guy perpendicular to the wind
and therefore there is no load on that guy, and the other guy is
away from the wind, also carrying no load from the wind.  The 
tension in the single guy (30 degrees from the wind) must be 
15% higher than the wind force due to the 30 degree offset.

I hope this "word" picture clarifies the situation.  I do not have
graphics capability on my E-mail.

de Tom - N4KG

On Fri, 14 Feb 1997 16:14:31 -0500 (EST) Pat Masterson <bat@grumman.com>
writes:
>
>I dont understand your thinking on this:
>
>On Fri, 14 Feb 1997, T. A. Russell wrote:
>
>> >From the geometry of 3 equally spaced guy wires, 
>> it is evident that the load carried by the guy wires 
>> IS EXACTLY EQUAL with the wind coming in-line with
>> a single guy or bi-secting a pair of guys.
>
> The guys on the back of the tower (lee side, down wind) will tend to
>slacken a bit as the tower leans toward them. The cable inline to the
>wind will obviously get tighter. The load on the cables (tension) cant 
>
>ever be equal with some wind blowing.
>
>> 
>> The WORST CASE is if the wind is in line with a FACE
>> of the tower, 30 degrees from a single guy wire, placing 
>
> The face of the tower is 60 degrees from the guy cable.
>
>> ALL of the load on that single guy (direction) with an
>> additional 15% load due to the geometry.
>
> If the wind is on a face, then the load is spread evenly to the 2 
>guys 
>attached to each edge of that face. They get tighter, and the back guy 
>
>gets looser. Where does that 15% get calculated from?
>> 
>> FOUR WAY guying prevents the 15% additional load
>> from geometric considerations, but puts an additional
>> load on the tower due to pre-tensioning. 
>
> Yep. More guy wires will add to tower compression.
>> 
>> de Tom - N4KG
>> 
>> 
>
>*-----------------------------------------------------------------------------*
>*  Pat Masterson  B38-01,  Northrop Grumman,     *  Ham:KE2LJ 
>*  Plant 1, South Oyster Bay Rd.,                *  Packet: 
>KE2LJ@KC2FD.NY 
>*  Bethpage, NY 11714                            *  President Grumman 
>Amateur
>*  email: bat@grumman.com   Fone: 516-346-6316   *  Radio Club  WA2LQO
>*-----------------------------------------------------------------------------*
>
>

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