Bracketing a self-supporting tower.
Tue, 20 Aug 1996 16:36:30 -0400
In a message dated 96-08-20 10:57:09 EDT, you write:
>If I put up a 40' to 50' self-supporting tower
>and bracket it to my house at about 15' just
>for a little added strength, will bracketing
>it cause any problems? This would not be a crankup.
>It would be Rohn 25G/45G, Universal aluminum, Titan, etc.
Hi, Gene --
First of all, a Rohn 45G only qualifies as a 'self-supporting' tower
within very narrow limitations (1.4 sq. ft. @ 80 MPH for 40 feet) and 25G
stretches the imagination (1.5 sq. ft. @ 70 MPH for 40 feet).
What is your county for wind zone?
Rohn specs also include loading figures for bracketed configurations as
well as self-supporting. Do you have the Rohn book? Call 309-697-4400 and
ask for the Consumer Products catalog. All of the answers are in there.
>I ask this because the bracket would cause additional
>downward force and less upward force on a tower
>and concrete base system designed for equal upward and
>downward forces. At least I think they would be equal.
The housebrackets are used for sideload and torsional strength and have
marginal effects on the uplift or compression capabilities of the tower. Did
I mention getting the Rohn book?
73 and good luck, Steve K7LXC
TOWER TECH -- professional tower supplies and services for amateurs