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> From: dennismc(--nospam--at)dennismc.com
> To: seaoc(--nospam--at)seaoc.org
> Subject: Re: Min. Code Design
> Date: Tuesday, April 22, 1997 9:38 AM
> 
> The policy I adopted several years ago is to do what I think is right.  I
> pay little attention to minimum standards indicated by the code.  Since
they
> don't figure anyway, I always calc things out and that is what goes on
the
> plans.  If the client doesn't like it, let them go somewhere else.  I'm
just
> doing my job and providing competent engineering judgement.

Ultimately, this should be the goal of every engineer. Get as much data
(research, empirical, etc.) as possible and then make a judgement.

 
> If you aren't accused of "overengineering", you are not doing your job. 
The
> contractors who make these statements know little to nothing about design
or
> codes.  They just know it's different than what someone else let them get
> away with.  I tend to try and educate people.  Once they understand why
and
> how, they are usually less critical.  Those who are concerned in quality
> appreciate it, those only interested in the bottom line usually
understand
> but still whine about it.  As long as there are bottom feeders out there,
> there will always be someone else that will do it cheaper and to lesser
> standards.  We need to stick together to raise the minimum standard of
quality.

It's been my experience that the only people who use the term "over
engineering" are those who are not engineers nor have any technical
background in engineering. The contractors' experiences are what he sees on
a job. If, on all the jobs a particular contractor works on, there are only
HD2As, as soon as he sees a set of plans with HD5As on them, he cries "over
engineered". Keep in mind also that the ones who are so-called concerned
about quality also do not have an engineering background, so they might
have a tendency to replace all of the HD2As on a job you specified with
HD5As. You might not think there is anything wrong with this, but the
construction cost goes up without benefit. If asked, you probably would
have recommended that they spend the extra money on diapragm blocking,
glue-nailing, special inspection or, heaven forbid, structural observation.

Hopefully, the ones interested in quality design will select a structural
engineer who shares the same interest and put their faith in his/her
design. I recommend that, before you suggest that we stick together to
raise the quality of the practice, we first must get together on what areas
of the practice needs raising first. I certainly agree that no one should
be intimidated by the term "over engineering". It is a term used by mostly
non-techical people intended to put the design engineer on the defense so
that the contractor can do what he learned when he started framing at 18.

> The term "overengineering" is a contradiction.    Any neanderthal can
stand
> on a log between 2 rocks and say it works.  It takes an engineer to
> determine the minimum size that will work.  Engineering means to
economize,
> so if you are "overengineering" you are being more economical?  Tell that
to
> the contractor and see if you confuse him.

I suppose that maybe the only legitimate application of the term
"over-engineering" would be in the case where a 4x10 calcs out and a 4x12
is specified. But, then again, only someone with an engineering background,
I believe, has the capability to evaluate the basis of the superimposed
loads, perform an analysis, select a lumber species and grade and those
"blankety-blank" modification factors that are different for every section,
evaluate deflection criteria as well as "fit" criteria. For example, I do
not think it is good engineering once the engineer has established the
design loads, etc. to multiply all moments, shears, etc. by say 1.25 and
then select a section based on the modified forces purely for the "just in
case" scenario. All loads and materials already have a factor of safety
built into them.

I have felt for a long time (particularly with seismic design) that we
probably do not have to increase design loads that much to ensure public
safety. If, after the project was designed, some methodology (say
structural observation or special inspection) was utilized to ensure all
hold downs were in and properly secured, all drag straps were installed and
attached to the proper members, etc. I think this is the area where
"quality in engineering" would be most significant. Oh, yeah, and to
prohibit Architects and junior CEs from signing structural plans (I almost
left that part out).

Regards,
Bill Allen



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From: "Bill Allen, S.E." <ballense(--nospam--at)concentric.net>
To: <seaoc(--nospam--at)seaoc.org>
Subject: Re: Min. Code Design
Date: Tue, 22 Apr 1997 13:03:32 -0700
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