In <199608132106.RAA11467@altair.cs.unc.edu>, on 08/13/96
at 05:06 PM, Nick England <nick@cs.unc.edu> said:
>Perhaps I'm missing something here. You guys ought to know all this
>better than me, a tower newcomer. The rough answer is that the rated load
>at 70 mph is 50% of the rated load at 50 mph. Wind loading is
>proportional to the square of the wind speed.
>With this approximation, rated load at 80 mph is about 40% of 50 mph
>spec, and rated load at 90 mph is 30% of the 50 mph spec.
In fact, impact pressure vs. true wind velocity is:
P = .004 V^2
where:
P -> pressure in pounds per square foot
V -> wind velocity in miles per hour
Thus:
20 pounds per square foot -> 70.7 MPH winds
80 mph winds generate 25.6 psf
100 mph winds generate 40 psf
--
73,
... Joe Subich, AD8I
<AD8I@ibm.net>
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