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
I completely understand your points. Definitely points I have been
considering.
My idea in my thinking was that having the extra guy set would increase
the
overall strength of the tower also increasing the wind load it could
handle.
For this tower to fall it would have to snap 8 guys on the way down.. My
other
concern is that the 2 sets of guys would be attached to 1 hook on the guy
bracket. If I'm to go with the idea of using a elevated guy anchor, would
this
need to be done on all 3 sides or just the side that has the shorter
distance?
What size post or I-beam is recommended. How deep do I bury it, and do I
need
to put it in at a 45 deg angle?
Thanks
Bryan
----- Original Message -----
From: <ve4xt@mts.net>
To: "Bryan" <bryanponder@sbcglobal.net>
Sent: Friday, September 17, 2004 4:46 PM
Subject: Re: Fw: [TowerTalk] Concrete anchors
Hi Bryan,
I think you're asking for trouble from a couple of angles
(no pun intended): first, you still don't have the optimum
tower to guy anchor space AND you want to go to a
greater enclosed angle than a 3-point system (120
deg.). I think you might get away with one or the other,
but not both.
I think barring an elevated guy anchor as suggested,
the only safe conclusion may be that your lot simply
won't accomodate a 120-foot guyed tower. Failing that, I
think you're going to want to get a PE wet stamp on that.
If you had to go to court after a collapse, I think the
plaintiff's lawyer would probably have you for lunch if all
you could provide in defence were replies to your TT
posts, particularly since in discovery, he'd probably find
the TT posts advising against this.
The good news is that you'll end up with greater
windload ability, which may help overcome any small
sacrifices in performance.
73, kelly
ve4xt
> From: "Bryan" <bryanponder@sbcglobal.net>
> Date: 2004/09/17 Fri PM 04:03:46 CDT
> To: <towertalk@contesting.com>
> Subject: Fw: [TowerTalk] Concrete anchors
>
>
> ----- Original Message -----
> From: "Bryan" <bryanponder@sbcglobal.net>
> To: "Tower (K8RI)" <tower@rogerhalstead.com>
> Sent: Friday, September 17, 2004 3:52 PM
> Subject: Re: [TowerTalk] Concrete anchors
>
>
> > The houses where I live all have varying amounts of
land. Some have a
> couple
> > of acres, some have a 1/2 acre like me. None of the
lots are square.. My
> > plan was to put an anchor on each corner. They
would all be about 85'
> from
> > the tower base. The problem is the sides. I would
have about 130 deg
> span,
> > but I would have a 4th guy set to help out with the
wind load. Unless of
> > course physics works against me and this ends up
causing too much stress
> on
> > the tower..
> >
> > My question with the anchor is how do I get a 7' rod
in a 4' hole at a 45
> > deg angle? According to the rohn drawing the
equilizer plate is almost
> > touching the ground.. I havent been able to find a
Rohn catalogue I guess
> > do to Radian buying them out.
> >
> > Thanks again for all the help.
> >
> > ----- Original Message -----
> > From: "Tower (K8RI)" <tower@rogerhalstead.com>
> > To: "Bryan" <bryanponder@sbcglobal.net>;
<towertalk@contesting.com>
> > Sent: Friday, September 17, 2004 3:26 PM
> > Subject: Re: [TowerTalk] Concrete anchors
> >
> >
> > >
> > >
> > >
> > > >The drawing I have for the gac305 anchor shows
them angled but doesnt
> > give
> > > >any hints on >how to do it. I know I need the hole
to be 3x3x4 but
> from
> > > >there I'm not sure what I need to >do to get the
anchor in the right
> > > >position.
> > >
> > > "As I recall" (which means you still need to look it
up in the ROHN
> book)
> > > the anchor comes out at 45 degrees and is far
enough from the tower to
> > point
> > > between the the top two guy sets.
> > >
> > > >I have a yard that measures 180' long by 80'
wide. I'm looking to
> install
> > a
> > > >120' rohn 25g. Can >I run 4 sets of guys off the
tower to make up for
> > not
> > > >having the 120 deg span?
> > >
> > > 120 feet on an 80 foot lot? You must not have
neighbors, or no setback
> > > rules. Even with 4 point guying you need the
anchors much farther out
> than
> > > you can get them for a 120 foot tower on an 80
foot lot. At a120 feet
> I'd
> > > say you need 100 feet from the tower for each guy
anchor. You can get
> by
> > > with a bit less, but that 120 feet on an 80 foot lot
scares me.
> > >
> > >
> > > Roger Halstead (K8RI, EN73 & ARRL Life
Member)
> > > N833R, World's Oldest Debonair (S# CD-2)
> > > www.rogerhalstead.com
> > >
> > > Thank you for your help
> > >
> > > Bryan
> > >
___________________________________________
____
> > >
> > > 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.
> > >
> > >
___________________________________________
____
> > > TowerTalk mailing list
> > > TowerTalk@contesting.com
> > >
http://lists.contesting.com/mailman/listinfo/towertalk
> > >
> > >
> > >
___________________________________________
____
> > >
> > > 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.
> > >
> > >
___________________________________________
____
> > > TowerTalk mailing list
> > > TowerTalk@contesting.com
> > >
http://lists.contesting.com/mailman/listinfo/towertalk
> >
>
>
___________________________________________
____
>
> 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.
>
>
___________________________________________
____
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
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.
_______________________________________________
TowerTalk mailing list
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http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
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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