That's interesting and gets us a little closer to the solution, provided the
rebar cage design is effective for tensile loads. If the tower manufacturer
has done this correctly, and the rebar is placed according to his spec, then
little is lost. BUT, I'm more worried about the concrete contractor, who
might say, "We never have to run rebar like that; as long as the footing
doesn't crack and the foundation doesn't shift, you're OK." Again, the
danger is in misapplication of requirements.
As to the low tensile strength of concrete, how does this square with all
the advice we have had that says it's OK to epoxy bolts into old bases and
depend on them to hold our towers up? Seems that scheme is a strong function
of concrete tensile strength!
BTW, Phil, KB9CRY, received the brunt of my post last night, but just
happened to be caught in the crossfire. He was not the originator of the
question, and I have apologized to him for spraying in his direction!
Chuck, N4NM
----- Original Message -----
From: "Richard Karlquist" <richard@karlquist.com>
To: "Chuck Lewis" <clewis@knology.net>; "Phil - KB9CRY" <kb9cry@attbi.com>;
"TowerTalk" <towertalk@contesting.com>
Sent: Wednesday, December 04, 2002 10:05 AM
Subject: RE: [Towertalk] Pouring base of tower
> > [mailto:towertalk-admin@contesting.com]On Behalf Of Chuck Lewis
> > Sent: Tuesday, December 03, 2002 9:54 PM
> > Subject: Re: [Towertalk] Pouring base of tower
> >
> > and the two
> > chunks of concrete
> > are being pulled apart. Now there might indeed be an epoxy
> > or similar
> > compound or a rebar configuration which will give the two
> > pours the tensile
> > strength of a single pour, but you need to ask the question
> > relative to a
>
>
> Yes, but the tensile strength of concrete is very low
> < 1000 PSI. The rebar provides most of the strength anyway even
> in a monolithic pour.
>
> Rick Karlquist N6RK
> richard@karlquist.com
> www.n6rk.com
> www.karlquist.com
>
|