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[TowerTalk] Multiple tower anchors and slopes

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Subject: [TowerTalk] Multiple tower anchors and slopes
From: konecc@mindspring.com (RJA)
Date: Mon, 20 Apr 1998 23:48:35 -0400
Agreed, I did the same with my 90 ft Rohn 45 tower.  The lower two sets of
guys are on one anchor, the top set is on a separate anchor.  I did this on
the side where, if the tower were to fall its full length, would fall on my
house.  The only failure scenario I could envision would be if a tree were to
fall and sever all 3 guy wires, which is pretty unlikely.  Makes me sleep
much sounder on windy, icy nights.

Multiple guy anchors also also makes installation over sloping ground easier,
since the angle of the guy wire can now be made correct with respect to the
tower, not to the ground.  If you have sloping ground and don't have any
friends who are surveyors, lay it out on a piece of graph paper (to scale)
with your best estimate of the ground slope in various guying directions.
>From the graph, determine how far each anchor point should be from the base
of the tower along the sloping ground.  For one set of guys I actually have
the top guy anchor closer to the tower than the lower guy anchors, but the
angles of the guys with respect to the tower came out almost perfect!  It
does mean, however, that on the downhill guy wires, the angle between the
ground and guy wire will be smaller than what it would be on flat ground.

For those using screw-in anchors, use a separate anchor for EACH guy wire,
you're then applying only ~1/3 the load that you would on a single anchor
(screw-in anchors are cheap!).  I  used screw-in anchors for that side --
there were so many tree roots that digging a foundation would have been
difficult, and once I started screwing in the anchors and felt them going
between the roots, I knew they were in there for good.  Be careful not to
break the welded "screw" when going into rocky (i.e. New England) soil.
Don't make your lever arm too long or hire too many strong helpers!

Rock outcroppings, if they're solid enough (mine weren't) also make good
anchors for guys, using drilled holes and steel (galvanized) rod.  K1RX did
that in his previous Connecticut location on several guy points and it worked
great (at least for the length of time he was there).  K1GQ in New Hampshire
has his in granite.  Am I starting a new thread?

Ahhh, the price to pay for a New England hilltop!  I'm always amused when I
see how easy towers are to put up on flat Midwestern soil, with flat ground,
no trees and good soil.  Is it any surprise there are relatively few
multiple-tower contest stations in New England?   Or is it that the
propagation is so good from here that we don't need them?

                                                                        --
Rich K1CC

k1cc@mindspring.com

> Jari:
>
>         I'd suggest that the friend add a second guy anchor point, INSIDE
> the existing guy anchor point, and transfer the existing lower guy wire
> to the new anchor point.  This makes virtually impossible a scenario in
> which a tower falls the full length of its height.  Do some thought
> experiments to see if you can come up with a scenario in which the tower
> falls the full length of its height in the direction of the complaining
> neighbor, and I'll bet you have to envision multiple simultaneous
> failures, a prospect far less likely than getting hit by a car on the way
> to buy milk and bread.
>
>         It may well be that no amount of arguing will satisfy the
> neighbor like a second set of guys.
>
>         Good luck.
>
>                                 Fred K1VR




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