Gene:
There was a Letter to the QEX Editor from DJ0IA [Jan-Feb 2003, p.60]
commenting on the fact that the calculations did not take into account the
effect of icing -- which is correct. The calculations provided by US Tower
also do not consider the effect of icing. There may be an additional error
that I am not aware of.
I did go through the mast stress analysis part and it looked OK to me but I
am not a structural engineering PE.
I also have the analysis for the US Tower HDX-572 done by them referenced to
the IBC-2006 spec. I inserted the US Tower parameters for the tower in the
Travanty program and got virtually identical numbers output for the moments.
One case that came out correctly does not guarantee that the program is
correct however. It is not a foolish thing to have a structural engineer PE
review the data for a serious tower installation. But, using a program like
Travanty's to get an idea of whether or not your plan is close to reasonable
is not unwise.
Tod, K0TO
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Gene Smar
> Sent: Tuesday, November 10, 2009 7:47 PM
> To: Tod - ID; 'Tommy'; towertalk@contesting.com
> Subject: Re: [TowerTalk] Basic tower installation question
>
> TT:
>
> Didn't someone here post a few years back that there was
> an error in Frank's spreadsheet calcs? Anyone know what they are?
>
>
> 73 de
> Gene Smar AD3F
>
>
> >
> > Frank Tranvanty, W9JCC, has written a very nice EXCEL
> spreadsheet that
> > allows one to calculate the stress on a mast with multiple
> antennas on it
> > and for various wind speeds. You enter the average wind
> speed [80 mph in
> > your case] and it will calculate the gust speed. It will
> solve the stress
> > on
> > the mast for antennas at various heights above the thrust
> bearing and with
> > different areas for the antennas. The program is written to
> allow one to
> > calculate tip over moment at the base of a telescoping
> tower but it will
> > function for non telescoping towers too.
> >
>
> >
> > Tod, K0TO
> >
> >
>
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