The anchors I ordered from UST for my TX472 were Type-F.
IIRC, they were 1-1/8" diameter x 27" L. Yes, I could've
researched them and saved some money by buying them
from someone else. However, the cost from UST didn't
break the bank, and they were a phone call away.
vy 73,
Bryan WA7PRC
________________________________
Date: Sun, 3 Nov 2013 01:13:53 -0500
From: Matt KM5VI
Subject: [TowerTalk] FW: Base Anchor Bolts
The link below shows some diagrams of different anchor bolt types. Which
ones do you have? The last HDX572 design calculations I have from UST
specify (6) 1" by 27" ASTM F1554, grade 55 (55,000 psi yield), with type E
block arrangement using a 2" square x 5/8" thick A-36 (36,000 psi yield)
steel block welded to the top die of the nut. Min embedment was 21". This
arrangement with a 5.5' x 5.5' x 7.5' footing was rated at 55,000 ft lbs
overturning moment in 100 psf soil.
http://stanley-sales.com/media/e5b0d8a7677e8f11ffff89b7ffffe904.jpg
I know that the ASCE revised the their standards a few years back resulting
in more conservative designs for anchor bolt pull-out strength. We
routinely run computer analysis for anchor pull-out these days considering
not only the embedment but also the overall geometry of the footing, The
last two shipments of grade 55 anchor bolts I purchased from my anchor
supplier were fabricated to the new ASTM F1554 standard and were Type F
with the heavy square block sandwiched between two welded nuts. FYI -
bolts I received from UST under the old design standards were ASTM A36
(36,000 psi) with Type D washer & nut welded to the base.
I have never heard of an anchor bolt pull-put failure on a UST. I would be
curious if anyone on the reflector has?
Hope this helps,
Matt
KM5VI
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