A Ufer ground is fine for a tower as long as it is not the only ground. You
still need ground rods outside of the tower base connected to the tower.
The J bolts for the tower mounting pad should be wired to the rebar inside
of the concrete. That is sufficient connection to the rebar for a Ufer
ground. You don't want any unconnected rebar gaps inside the foundation that
could arc.
73
Gary K4FMX
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Bill Aycock
> Sent: Thursday, March 11, 2010 10:50 PM
> To: wisecrafter@suddenlink.net
> Cc: Towertalk@contesting.com
> Subject: Re: [TowerTalk] tower & antenna project questions
>
> Thank you Jan--
> I thought it was at least that old. That opinion has been disproved many
> times, which is why the ARRL took the reference out.
> I have seen concrete explode, and it took a LOT of local heat to do it.
> On
> the occasion when I saw it, it was Rocket fuel. The ground system
> described
> is, essentially, an "Ufer" ground, where there is connection between the
> rebar cage and the ground system. The Army uses this system to protect
> explosive storage facilities. Successfully. I worked in one, designing
> Rockets, for 38 years. Go to the Wikipedia and look up Ufer.
> The Lightning caused steam explosion is a myth. What IS bad, and can
> cause
> concrete cracking, is having rebar in contact with both the ground and
> the
> cement at a boundary. In this case, the steel rusts, admits water, and
> cracks appear on freezing. They use Copper at the transition to stop
> that.
> I have not seen a documented case of a Lightning-caused concrete
> explosion.
> ----- Original Message -----
> From: "Jan Wise" <Wisecrafter@suddenlink.net>
> To: "'Bill Aycock'" <billaycock@centurytel.net>
> Sent: Thursday, March 11, 2010 7:31 PM
> Subject: RE: [TowerTalk] tower & antenna project questions
>
>
> > That came out of the ARRL Antenna Book 16th edition Copyright 1991.
> > It is under bases for towers in the index. Pp 22-9 TOWER BASES
> >
> > -----Original Message-----
> > From: Bill Aycock [mailto:billaycock@centurytel.net]
> > Sent: Thursday, March 11, 2010 5:20 PM
> > To: wisecrafter@suddenlink.net; Tower and HF antenna construction
> topics.
> > Subject: Re: [TowerTalk] tower & antenna project questions
> >
> > That must be an OLD handbook. Can you give me the year, chapter and
> page
> > where this old wives tale is? I'd like to find it in print, jut once.
> > Bill--W4BSG
> >
> > ----- Original Message -----
> > From: "Jan Wise" <Wisecrafter@suddenlink.net>
> > To: "'Tower and HF antenna construction topics.'"
> > <towertalk@contesting.com>
> > Sent: Thursday, March 11, 2010 4:22 PM
> > Subject: Re: [TowerTalk] tower & antenna project questions
> >
> >
> >>I am not sure, but I think if you look at the Hand Book It will state
> that
> >>you do not want the tower or anything else to be grounded that goes
> >>through
> >
> >>concrete. The reason being that a hit from lightning
> >> Will cause the concrete to explode. If I am wrong someone please let
> me
> >> know !
> >>
> >
> >
> >
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> >
> >
> >
> > __________ Information from ESET NOD32 Antivirus, version of virus
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> > database 4937 (20100311) __________
> >
> > The message was checked by ESET NOD32 Antivirus.
> >
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> >
> >
>
>
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