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## Walk Under Guy Anchors:

 To: Walk Under Guy Anchors: w5fl@flash.net (Wendell - W5FL) Mon, 16 Dec 1996 18:37:13 -0600
 ```I ordered the standard Rohn 45 Foldover double guy kit with the 64 foot = tower, but want to use walk under guy anchors (instead of the 4 screw = anchors they furnish) to get the guy wires up so I won't run into them. Question: Any suggestion on how to best adapt 4.5 inch pipe anchors for = attaching the Jaw of the 1/2 in x 12 turnbuckles.? =20 I have drilled the four (4) anchor holes on a 25 foot radius as Rohn = recommends (35 ft between anchors). The guy anchors will be 4.5 inch od = 1/4 in wall oilfield pipe 10 feet long. The holes are 18 inch in = diameter and 5 1/ 2 feet deep (IN SOLID ROCK starting at 24 inches). = This will leave the pipe sticking out of the ground 4 1/2 feet (no rebar = in anchor holes). I need to weld an adapter of somekind to the pipe such = that a 1/2 inch hole can be made to mount the jaw of both 1/2 x 12 inch = turnbuckles Rohn furnishes. Their guyline is 1/4 inch EHS with guys at = 29 and 58 feet. The base is 30 inches in dia x 4 1/2 feet deep (also in = solid rock starting at about 24 inches). =20 If you want to comment on my calculation, or can find an error in them, = I would appreciate all suggestions as I hope to pour concrete next week: = =20 Rohn 45 Foldover Tower at 64 feet. =20 Antenna load =3D 17 sq ft 1 set control cables & feedlines per leg (7/8 + 1/2) Windspeed 112 mph =3D 50 psf ( I believe 30 psf is probably adequate for = most conditions but I lost 40 sheets of plywood with roofing attached = off my house last year in a Texas thunderstorm!) Note: Maximum load occurs in line with guy wire where it is 30 deg from = guy wire for 3 guys. Loading in top set of guys at 58 feet =3D 1713 # (6650# breaking = strength for 1/4 inch) Loading in lower set at 29 feet =3D 1308 # (Turnbuckles rated = at 11,000# break) Anchor uplift =3D 2347 # (about same as 150 ft tower with guys at 80% of = height) Base Down Force =3D 9389 # (Rated at 18,960#) I guess I have to also finalize the grounding system for the tower = before I pour concrete: I have a lot of questions about the best way to = ground the tower and anchors based on polyphasers book when you have = 24-30 inches of gravely/rocky soil on top of a solid rock ledge that is = at least 9 feet thick-but that is another story. Wendell Wyly - W5FL w5fl@flash.net -- FAQ on WWW: http://www.contesting.com/towertalkfaq.html Submissions: towertalk@contesting.com Administrative requests: towertalk-REQUEST@contesting.com Problems: K7LXC@contesting.com Sponsored by Akorn Access, Inc & KM9P ```
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