Alton,
Take great care installing elevated guys. There are a lot of vector forces
to account for and Dave is right...get an engineer to do the design. I did not
do that thinking that 4 feet in concrete and 6 feet above ground would do. It
did not! Do not use backyard engineering methods.
I used 10 foot steel 8" pipes that were schedule 80....filled with concrete.
The pipes bend, but the earth moved. You need a massive amount of concret
under elevated guys. I did not have enough concrete under mine. I need to dig
them out and redo them, but then again that is a lot of work. You need to
account for the "leverage" that is applied to the top of the elevated guy point
and what it is doing through the fulcrum into the ground. The ground cannot
move and the pipe should not bend. Most of the forces are along the line of
the guy line...of course.
If I were to do it again, I would triple the amount of concrete and make
provision to weld on some braces that would be in the ground along the lines of
the guy wires so when the energy is transmtted through the guy lines the braces
would have to bare down from the fulcrum and the other would bare up. The
braces would be in the ground....and in concrete. Think of burying a "T"
upside down in the ground and the pouring concrete. The top of the "T" would
be in line with the guys. That would give the elevated guy point something to
push against in two directions...down thrust and up trust. Gobs of concrete
too.
I would also would have used "H" steel beams with an extra 1/2" plate steel
welded between the verticle component of the "H".
Dave is correct. Get a PE to do the work. Well worth the dollars.
Lee - K0WA
In our day and age it seems that Common Sense is in short supply. If you don't
have any Common Sense - get some and use it. If you can't find any common
sense, ask for help from somebody who has some common sense.
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