Hey Keith,
Thanks for the pics. How far out are your anchors from the base?
----- Original Message -----
From: "Keith Dutson" <kjdutson@earthlink.net>
To: "Towertalk" <towertalk@contesting.com>
Sent: Friday, September 17, 2004 10:57 PM
Subject: RE: Fw: [TowerTalk] Concrete anchors
> I agree that elevated guys should be extra strong to avoid movement during
> high winds. I chose 8 foot steel pipe with three feet in the concrete. The
> pipe is 4.5 inches OD with .25 inch wall. The three poles were hot dip
> galvanized before installation. Each is set in 4 yards of concrete
> (overkill) and the pipe is filled with concrete to increase bending
> resistance. I was able to observe the windward pole during a squall that
> had 70 MPH gusts at the top of the tower. There was no apparent flex at the
> top. The guys are pre-loaded at 600 PSI. The tower is 150 feet of Rohn
> 45G.
>
> Here are a few shots of one of the poles. One of the snapshots shows an
> apparent bend, but this is just an aberration of the camera lens.
>
> http://www.dutson.net/transfer/HamRadio/TowerGuys/
>
> Keith NM5G
>
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Tower (K8RI)
> Sent: Friday, September 17, 2004 6:51 PM
> To: Bryan; towertalk@contesting.com
> Subject: Re: Fw: [TowerTalk] Concrete anchors
>
> Something to remember about elevated guy anchors. They really need to be
> massive and strong. The elevated part needs to be heavy structural steel
> capable of holding the guy tension and load without give. I use 5" steel
> pipe that is reinforced and it sets in a bit over 2 yards of concrete. Were
> I to do it again I'd use at least 3 yards and my tower is only 100 feet with
> the anchors out 80% or 80 feet.
>
> I'm a bit short on ambition to run the calcs for stress and anchor points on
> the tower. Besides I haven't had to do any of that math since I graduated
> from college.
>
> However with the anchors in close and of unequal lengths I'd expect to see
> some twisting moment added in addition to the side load with wind.
>
> Roger Halstead (K8RI, EN73 & ARRL Life Member) N833R, World's Oldest
> Debonair (S# CD-2) www.rogerhalstead.com
> [snip]
>
> _______________________________________________
>
> 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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_______________________________________________
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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