[TowerTalk] concrete base for Rohn 140 foot SSV

[john at kk9a.com]

You have a 140 foot self supporting tower weighing over 3000 pounds and 
you're looking on towertalk for someone to say that it's OK to use less then 
the recommended amount of concrete?  I'm sure that an engineer can change 
the base to a smaller square and deeper, but that would require some 
engineer costs and I think that it is easier to dig the relatively shallow 
hole that you described.   SSV is a nice tower, don't skimp on the 
foundation!

John KK9A



To: <TowerTalk at contesting.com>
Subject: [TowerTalk] concrete base for Rohn 140 foot SSV
From: "Marvin Gorden" <mg at harvesting.com>
Date: Sat, 15 Jan 2011 14:25:06 -0600
List-post: <towertalk at contesting.com">mailto:towertalk at contesting.com>

Looking at the Rohn base specs, I am quite surprised at the requirements,
assuming I read it right.  For a base, without piers, the specs call for a
14'-3" X 14'-3" X 4' concrete base ( 30.1 cubic yards).



To me that seems like considerable over kill.



My tower has 8N, 7N, 6N, 5N, 4N, 3WN and 2W sections.



I looked at a 140' SSV installation a few miles away from here and that base
is 7'-9" square.  I don't know if that sets on piers or how deep it maybe.



Any qualified comments would be appreciated, before I start digging.



KC9VF