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.
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