The tower we put up was a Tristao (aka USTower) HBX-555. Because the
wind rating here is 96 mph, the PE determined the base had to be at least
10 ft into bedrock. The reason The base was shaped like a 17ft x 30"
cassion is that the building pad at the site was 5 ft of compacted soil on
top of bedrock.The PE made it round for ease of digging and 17 ft long was
to compensate for the loss of overturn momentum resistance incurred by
the smaller diameter. The end result was to require less concrete than a
comparable square block, which would have been as as much as 6 or 7
cubic yards or concrete. As it was, only 4.5 cubic yards was required and
we dug the hole in about an hour using a backhoe equipped with a hydraulic
At 07:33 PM 11/08/1999 +0000, M Goins wrote:
>what in heaven's name did you put up that needed a 17 foot hole?
>and how in the world did you get it dug? I haven't had a tower up since the
>late eighties and I'm putting up a US Tower, cu/to mast (60 footer). It has a
>base of 3X3x5'6" and I'm not sure how to get it dug fairly square.
>homebrew vertical @25 feet
>(2 el quad at 60' soon, along with a zepp at 50')
>QRO at 5 watts, Qrp at 1 most of the time
>Get free email and a permanent address at http://www.amexmail.com/?A=1
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