[Top] [All Lists]

Tower Ratings - a data point

To: <>
Subject: Tower Ratings - a data point
From: (Mike Meehan)
Date: Thu, 19 Dec 1996 16:53:25 -0800

Hi All,

I have calcs for 3 US tower designs. (Actually one was for
an old Tristao/Pratt design.) The good news is that they are
moving to computerize the calcs. They use a spread sheet
for many of the calcs used in the latest set I have...

If you want a `back-of-the-envelope' calc of what a 50MPH
tower will hold at 70MPH, just cut the load area in half...
So 30ft^2 at 50MPH will be about 15ft^2 at 70...But as someone
pointed out, it will be somewhat less than 1/2 because the load
due to the tower itself will also increase.

In all 3 sets of calcs the failure mode is the leg compressive
strength, and in a section in the top half of the tower. The
laps as I recall have a pretty good margin...

Something to watch out for is that some of the sections can have
one or both:

    leg inserts
    extra bracing

but only over the intended lap area. So if you crank down your tower
a little bit you might actually be introducing a condition where
you are defeating the lap engineering---you have a weaker 

Sorry to add complexity to the mix...BTW, it wasn't a stupid
question at all! no such thing...

Kindest Regards,

FAQ on WWW:     
Administrative requests:
Sponsored by Akorn Access, Inc & KM9P

<Prev in Thread] Current Thread [Next in Thread>