I understand the logic in increased building code requirements for public
safety. But from what I have read tower failures are generally from the
towers themselves and not specifically from the concrete bases.
Increasing the size and depth of the concrete base seems to be going the
wrong direction. If you want that extra margin of safety perhaps it is the
rated capacity of a tower that should be upgraded.
I have installed several towers for my own personal use over the past 30
years and each concrete base installation requirement is bigger and deeper
than the last.
Hmmm...I wonder if I can find any of my original concrete base drawings?
73, Bob - AI7M
----- Original Message -----
From: "Jim Lux" <jimlux@earthlink.net>
To: "Robert Shauger" <rgshauger@myyellowstone.net>;
<towertalk@contesting.com>
Sent: Sunday, September 07, 2003 1:08 PM
Subject: Re: Fw: [TowerTalk] Re: Tower base hole?
> probably a reflection of increasing building code requirements for things
> like seismic loads, wind loads, etc. Over the past 20-30 years there has
> been a gradual shift in building codes from establishing a "bare
minimum" -
> assuming a competent and responsible architect/builder/etc will actually
> design better than code to a more "guaranteed safety". There have been
> lots of lawsuits, threats of lawsuits, etc. where it winds up being an
> argument about whether "built to code" guarantees "safe" or whether "safe"
> relies on additional professional judgement.
>
> There has also been a troubling (to me, as a PE) trend where clients
demand
> to know why you put anything more than the bare "code required minimum"
into
> a design, particularly if it increases cost and either a)threaten to take
> their engineering business elsewhere or b)threaten to sue for malpractice;
> neither of which is particularly pleasant.
>
> And, of course, the knowledge of actual hazards and their societal costs
is
> increasing. When a hurricane wipes out a huge number of houses in FL,
> causing insurance companies to stop writing policies or go broke, there's
> usually an outcry to improve standards to limit the liability. (of course,
I
> think it's crazy to build on the beach in hurricane country anyway.. just
> like building in the bottom of the ravine around here in southern CA..
That
> 1000 foot deep canyon didn't arise by fiat...)
>
>
> Jim Lux, W6RMK
>
>
> ----- Original Message -----
> From: "Robert Shauger" <rgshauger@myyellowstone.net>
> To: <towertalk@contesting.com>
> Sent: Sunday, September 07, 2003 11:13 AM
> Subject: Re: Fw: [TowerTalk] Re: Tower base hole?
>
>
> > I have noticed many of tower bases designs are being redesigned for
larger
> > and deeper bases for the exact same tower model.
> >
> > Is there a reason for this, other than manufacturing liability issues?
> Just
> > curious.
> >
> > 73, Bob - AI7M
> >
> >
> > ----- Original Message -----
> > From: <K7LXC@aol.com>
> > To: <ve4xt@mts.net>; <towertalk@contesting.com>
> > Sent: Sunday, September 07, 2003 6:17 AM
> > Subject: Re: Fw: [TowerTalk] Re: Tower base hole?
> >
> >
> > > In a message dated 9/6/03 9:12:07 PM Pacific Daylight Time,
> ve4xt@mts.net
> > > writes:
> > >
> > > > My bigger concern with an 8-foot deep hole isn't with how to dig it,
> > but,
> > > > depending on the soil, how to keep it from collapsing in on me as I
> do.
> > > >
> > > > For that reason, anything that allows you to dig the hole without
> being
> > in
> > > > the hole is a good thing.
> > >
> > > Good point. US OSHA rules say that any hole deeper than 4-feet
needs
> > to
> > > be shored up to prevent cave-in injury. Any time you're in over your
> head,
> > it's
> > > dangerous.
> > >
> > > I have a big problem with difficult and/or dangerous hole designs.
> US
> > > Tower and Trylon have some stupid designs. Trylon wants you to bell
out
> > the
> > > bottom of their bases which means you have to be in a 5-1/2 to
> 6-foot-plus
> > hole and
> > > dig the bell portion out by hand. In some soil conditions this is
almost
> > > impossible. In all cases it's potentially dangerous. UST wants you to
> dig
> > a
> > > 4x4x7-feet deep (or even 3x3x-6-feet deep) hole. These bases were
> designed
> > by
> > > engineers sitting in air-conditioned offices who never have tried to
> build
> > one of
> > > these things. I much prefer having a shallower but wider base - easier
> to
> > > excavate and not dangerous at all. Don't get me started!!!!
> > >
> > > You can have your PE design the base to your particular
> configuration
> > and
> > > requirements so you don't have to put up with a stupid factory design.
> > >
> > > Cheers,
> > > Steve K7LXC
> > > TOWER TECH --
> > > Professional tower services for commercial and amateur
> > > _______________________________________________
> > >
> > > 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.
> > >
> > > _______________________________________________
> > > TowerTalk mailing list
> > > TowerTalk@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> > _______________________________________________
> >
> > 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.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
> 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.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
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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