I have seen an increasing number of posts such as the one below, where the
text is all compressed into one hard-to-read paragraph. Anyone know what's
going on? Maybe it's something on my end? I don't think it's limited to
Towertalk, but it may be limited to contesting.com. I'm not sure.
Dave Hachadorian, K6LL
Yuma, AZ
-----Original Message-----
From: Byron Tatum
Sent: Thursday, April 4, 2019 7:25 AM
To: Towertalk Reflector
Subject: [TowerTalk] 130' 45G Gyued Tower Questions
Hello- I have some questions regarding the effects seen on anchor rods
when installing first level of guys on a 130' 45G tower: The tower
is installed per Rohn 130 MPH specs, using same spacing, dimensions and
angle of anchor rod (38 deg). The anchor rod is made identical to the Rohn
GAC5655TOP being 10' long, 1.25" high strength rod, 1/2" 50 KSI plate at top
end of rod but with only 3 drilled 13/16" holes for turnbuckles, hole
spacing same as Rohn (5655 anchor has 5 turnbuckle holes) and concreted in a
concrete anchor built per Rohn AB3 dimensions. I have the tower
free-standing at 41' right now using a 5' concrete base section. A guy
bracket was installed at 35' per Rohn spec and I attached the guy/turnbuckle
to bottom hole in anchor rod plate and tensioned to around 600#. I am seeing
the anchor rods bend downward to an angle of around 30 deg as I increase the
tension on guy wire. It appears the rods have a very slight, just barely
perceptible bow in them, possibly from the wrenching action of the pull
being from several inches below the rod center (as plates are welded to rod
and not pivoting). I left the "slots" cut in ground (where
anchor rod angles upward from top of concrete to surface of ground) unfilled
as I wanted to be able to observe the effects on them and to install
protective sheaths on them, where they exit the ground, when tower is
finished plus to backfill these with clean sand. The rods were tarred and
wrapped for corrosion protection. I backed the turnbuckles off to a
much less guy wire tension in order to reduce the downward pressure on
anchor rods and to allow me to install cribbing under the turnbuckle plates
to restore my anchor rod angle back to 38 deg. This is the first
tower that I have installed with fixed turnbuckle plates welded on an anchor
rod. It seems that all of the ones in past had the pivoting turnbuckle
plates and I did not notice these effects as the plates pivoted way upward
with only bottom guy wire attached. So my questions are --1. Has
anyone else observed these things in installing a similar tower? Possibly if
I had backfilled the anchor rods these effects would not have been as easy
to detect.2. Would anyone have an opinion regarding using strong cribbing
under the turnbuckle plates in order to maintain original installed rod
angle of 38 deg. as I restore tension to around 600# on bottom set of guy
wires? I imaging that when I get the second level of guys
installed, of which turnbuckle holes are centered on ends of anchor rods
themselves, the rods will be pulled upward, closer to the installed angle of
38 deg, and with installation of top set of guys all will balance out for
rod angle of 38 deg. My first experience with fixed turnbuckle
plates on anchor rods. Thanks for any comments or advice.Byron W5FH
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