That is all I was saying and that this is unnecessarily confusing to the new
guys.
No way more than some very, very limited number of people would ever have
reason to doubt the quality of concrete mix coming from a commercial vendor
or have to go to such extremes. It is unnecessary. Commercial concrete guys
do that for a living and pour lots of concrete, and I seriously doubt if
less-than-superb concrete could make a difference with most ham
installations. In 35 years at this I have never heard of a ham losing a
tower due to concrete failure because the slump wasn't right or whatever.
As Roger said so simply - the base keeps the tower from sinking or skidding
sideways. If self-supporting, it needs to be adequate to handle that too.
It's not rocket science for most installations and slump/concrete
compression figures et al is totally unnecessary and confusing in most
situations. I don't have Arecibo here - I have a ham radio installation
crank-up that will hold a quad and a wire or two.
Do it right - according to the manufacturer's spec or some engineer's
drawings, but take a deep breath and lighten up some.
Mike, k5wmg
Pipe Creek, Texas
Green cars, slow boats, big dogs, old trucks, little radios, and summers off
to write
On Thu, Sep 2, 2010 at 1:35 PM, Roger (K8RI) <K8RI-on-TowerTalk@tm.net>wrote:
> I know my response will probably give some apoplexy but...<:-))
>
> On 9/2/2010 11:43 AM, k2qmf@juno.com wrote:
> > Yeah!! Talk about overkill........
> >
> >
> > On Thu, 2 Sep 2010 10:34:23 -0500 Michael Goins<wmgoins@gmail.com>
> > writes:
> >> Good Lord. Whatever happened top Joe Average Ham and just pouring
> >> concrete
> Concrete?
> >> for a base? I can see all this if you have an gigantic hundreds of
> >> feet high
> >> superstation, but the average guy doesn't need to have his concrete
> >> analyzed.
> >>
> >> You dig the hole the tower manufactuer specifies and you use the
> >> rebar/cage
> Rebar?
> >> they say. You guy correctly if it is guyed tower.
> Yes
> >> You add concrete
> Why?
>
> If the tower is no more than 50 or 60 feet with good guying and say a
> tribander or even a tribander and WARC7 or VHF/UHF antennas of
> reasonable size above it, I've gone back to using "dirt bases" (highly
> dependent on soil conditions) although I weld up my own which are far
> more substantial (and heavier) than the commercial ones.
>
> For a guyed tower, the base only does two things...well three counting
> supporting the tower. It keeps the tower from sinking, and it keeps the
> base of the tower from moving sideways. In good soil and a light tower
> load this is easy to do. ROHN even sold a "dirt base" for years.
>
> However for larger systems and self supporting, I'd go to the larger
> concrete base with rebar.
> >> and make
> >> sure there aren't voids. 99.999% of us need nothing more than that.
> >>
> I seriously doubt even 60 or 70 % go that far, at least not from the
> average 40 to 50 footers I've seen.
>
> 73
>
> Roger (K8RI)
> <snip>
> _______________________________________________
>
>
>
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