If you run into bedrock or granite ledge (as we call it here in The
Granite State), just drill into it with a rock drill (I think you can
rent them at the Home Despot). Then put rebar in at multiple angles and
cement them in. Next pour the concrete anyway (you won't need as much)
because of the ledge. What you'll have is tower bases and guy anchors
that are part of the ledge and are much stronger than a concrete base alone.
Most of my guy anchors and bases have this in them, although they turned
out to be just deep enough for the Rohn Specs without them. I put the
rebar into the ledge anyway.
From the man who brought you (or at least paid for) Marchand v. Hudson,
Jerry Keller wrote:
>Many thanks to all those who provided answers to my questions about
>concrete. The concensus was that 4000 lb concret with a 5" slump would do
>the job best, and that's what I'll be doing. Now if only I can get the hole
>6 feet deep without running into bedrock or something I can't move!!
>Cheers & 73, Jerry K3BZ
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
>questions and ask for Sherman, W2FLA.
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