Specific design info from the manufacturer, in my mind, would trump
anything from a general code manual like the UBC that I referred to. My
point in my e-mail, though, was that a circular hole that's the same
diameter as the square's side (the circle fits inside the square) is NOT an
equivalent design, all other things (depth, reinforcing, etc.) being equal.
The drilled hole must be the dimension of the square's DIAGONAL. (The
square fits inside the circle.)
For your design, the manufacturer recommends a depth of five feet for
the square hole and six feet for the round hole. Not apples to apples. The
equivalent diameter for a round hole and SAME depth would be 5 feet X
SQRT(2) = 7 feet diameter. That's if you wanted to keep the SAME five foot
depth of the square hole.
You're able to use the smaller diameter hole (4 feet vs 7 feet) because
you dug down deeper (6 feet), per the manufacturer.
Gene Smar AD3F
P.S. There I go again - number-crunching.
From: Tom Branch <firstname.lastname@example.org>
To: EUGENE SMAR <email@example.com>; firstname.lastname@example.org
<email@example.com>; Dino Darling <firstname.lastname@example.org>
Date: Sunday, March 30, 2003 8:59 PM
Subject: Re: [TowerTalk] Round Hole vs Square Hole...
>I contacted the tower manufacturer and was told that I could use a square
>hole that was 5 by 5 by 5 or a circular hole that was 4 by 6. The square
>hole is 125 cubic feet and the round one is 75 cubic feet. The square hole
>requires 4.6 yards of concrete and the round one requires 2.75 yards. I
>the round hole--let's hope they knew what they were doing...
>73 de Tom, K4NR
>----- Original Message -----
>From: "EUGENE SMAR" <email@example.com>
>To: "Tom Branch" <firstname.lastname@example.org>; <email@example.com>; "Dino Darling"
>Sent: Sunday, March 30, 2003 7:05 PM
>Subject: Re: [TowerTalk] Round Hole vs Square Hole...
>> A circular hole of adequate size actually requires MORE concrete
>> square hole of adequate size.
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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