Trylon / Titan Towers??

[David L. Thompson]

>>                      TITAN MAXIMUM WIND THRUST VALUES
>>
>>MODEL  MAX HEIGHT         70MPH              85MPH
>>-----  ----------    ---------------    ---------------
>>T200      96ft       200lbs/15 sq ft          n/a
>>T300      88ft       300lbs/22 sq ft    110lbs/ 6 sq ft
>>T400      80ft       460lbs/34 sq ft    240lbs/12 sq ft
>>T500      72ft       600lbs/45 sq ft    450lbs/22 sq ft
>>T600      64ft       800lbs/60 sq ft    700lbs/35 sq ft
>>T700      56ft      1000lbs/80 sq ft    900lbs/45 sq ft
>>T800      48ft      1300lbs/99 sq ft   1130lbs/58 sq ft
>>
>
>Hi Scott,
>
>I noticed that when you divide the "lbs" by the "sq ft" you get about 13 at
>70 mph and about 20 at 85 mph using the data in the above chart.  An old EIA
>wind chart that I have in an old Rohn catalog says 70 mph is 19.6 lb/sq ft
>and 85 mph is 28.9 lb/sq ft.  The implication is that maybe the "sq ft"
>rating is a little too high for the "lbs" number.  But maybe my data is just
>too old and the EIA chart has not been found to be accurate.
>
>What do you think K7LXC?
>
>Stan  w7ni@teleport.com

I would think that the chart from each manufacturer would be different due
to design specs.
There is some correlation between weight (down moment) and square feet, but
normally a tower mfg designs to a certain dead weight limit then looks at
side moments or max sq ft.    The Rohn BX series can handle 10 sq feet but a
max of a 10 foot boom.

Weight is strictly a discrete  measurement.   Sq ft is calulated from wind
resistance on the elements and boom.    This will vary from one manufacturer
to another unless they use the exact same design. 

Rohn told me that the EIA spec is a respected guideline.   Trylon is just
more conservative.

Dave K4JRB