>In a message dated 98-03-12 01:17:52 EST, rmidgett@edge.net writes:
>
>> Each pipe is between 7 & 8 feet long, with 5 feet
>> of the pipe in an eight inch diameter hole filled with Quickcrete to within
>> 2-3" of the ground surface.
and K7LXC says:
> IMO putting concrete in a pipe is superfluous and doesn't add any
>appreciable added strength to the pipe.. Say you have a column of concrete 4
>inches in diameter and it's 3 feet tall standing vertically. What happens when
>you let go and the concrete column hits the ground? Right - it shatters.
>That's what it'll do if there's any compression when it's inside a pipe. It
>doesn't really do anything.
W7NI thinks:
Filling a pipe with concrete makes it very difficult to kink it since
concrete will not compress, even if it is broken. If you take a piece of
pipe with nothing inside it and bend it sharp, like right over the top of
your tower or right where it exits the concrete at the ground, it tends to
kink with one side bending inward. If there is concrete inside the pipe, I
believe it would take A LOT more force to bend it such that it actually
breaks since it can't really kink. You can still put gentle bends in pipes
filled with concrete but it is the sharp kink and sudden drastic failure
that I would hope to prevent with concrete inside the pipe. Just my
opinion. I could be wrong . . .
Stan w7ni@teleport.com
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