"maybe" it has enough dead weight that if on top of the ground it would
resist being pulled sideways. but would it have enough overturning force
for a lever arm of however many feet stick up from the concrete to hold 5
guy wires each tensioned to about 600# (assuming 1/4" ehs and typical
instalation for rohn towers). this would be 3000# (something less
actually but depends on adding up all the vectors) of static load, then
add additional force for max wind load on the upwind side, antenna area
and placement, ice area, etc... apply that summed up force to the end of
the lever arm created by the pipe and see if it wouldn't turn over that
block if sitting on the ground. i would take any comment like that with a
grain of salt until shown the calculations done by someone who deals with
that type of guyed structure regularly... the forces are way higher than
they look even on a calm day.
> I use pipe. Each pipe is buried about 5 feet with a few inches of gravel
> at
> the bottom and about 4 yards of concrete. A friend who is also a CE for
> the
> county came by to see the installation just after the concrete was poured.
> He laughed when I asked him if he thought I had enough concrete for a 150
> foot tower. He said 4 yards of concrete has sufficient weight to hold the
> tower even if poured on top of the ground. :-)
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of
> garyejones@cmaaccess.com
> Sent: Thursday, October 21, 2004 7:34 AM
> To: towertalk@contesting.com
> Subject: [TowerTalk] elevated anchor guy points
>
> I purchased a house last year as a compromise house that was OK but didn't
> have some things (like more land) that I really wanted but I needed to get
> into a house for a new job in a new city. I still have not found the
> land/house combination, and need to get a tower or two up in the air. Main
> problem is that I have a 50 foot gas pipe line running along one edge of
> the
> property. If I put up towers here, it would be best to locate one or two
> of
> the guys along the property line. I have done some preliminary exploration
> and the gas pipeline company may give me a few feet of space at the edge
> of
> their easement which would let me sink an anchor point/points. The problem
> is they would like to minimize the "permanent" stuff over their easement
> iin
> case they need to get to their pipeline.
>
> What would help would be to elevate the guy points above ground. Five or
> six
> feet would be reasonable and make them happy.
>
> I have previously used back guyed drill stem buried in concrete to anchor
> some towers, but was never happy with it. Towers always stayed up but I
> just
> would have liked the additional security. My towers are 100 and 120 feet
> tall sticks of Rohn 45 and I will run some big antennas on them (two or
> three monobanders on each of them).
>
> Does anyone have suggestions on what and how to do elevated guy anchor
> points which will hold the load of the tower? Has anyone had an engineer
> do
> the calculations for a steel I-Beam buried in concrete or steel pipe? I
> can't use a back guy, so the anchor has to take the whole weight of the
> tower and stay where it belongs. Can anyone tell me about their
> experience,
> or how to calculate the loads to figure the minimum specs needed or is my
> only answer to spend some money on an engineer?
>
> Thanks
>
> 73
>
>
> Gary W5FI
>
>
> _______________________________________________
>
> 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.
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