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Re: Ethics 101

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I will offer this personal scenario as an indication of the "grey" zone.

A school building in central Kansas was originally constructed in 1910.
Concrete walls and concrete floor frame clad in brick with heavy timber
roof.  The wood roof truss over the stage in the auditorium was altered
from the original plans during construction and the bottom chord was
constructed 5  2x12's bolted together in lieu of a single heavy timber.
The 2x12's were not the full length of the bottom chord and the ends
were randomly spaced.  When analyzed the numbers did not work.
Apparently the truss settled on the brick wing walls at each end of the
stage.

A remodel in 1959 removed the brick wing walls.  The truss sagged about
6 inches.  Additional steel reinforcing was added in 1959, but it
stopped one panel short of the end.  In 1987 a new head of maintenance
was hired, he noticed the sagging truss in September of 1989, he hired a
structural engineer to perform an evaluation (school was in session).
The structural engineer performed a visual evaluation and advised to
evacuate immediately, cordon off the building and demolish the entire
school ASAP (the conservative approach).  The school board chose to
obtain a second opinion from a larger (deeper pocket) firm.

I inspected the school on a Friday and evaluated the problem.  I
concluded that the structure could easily be shored, and be safe enough
to remain in session while a permanent repair was designed and
installed.  The structure was shored that weekend.  I had to present my
findings in front of an emergency school board meeting, with anxious
parents, and a dubious press.  Some class rooms were closed off, but the
school remained in session.  Eventually the permanent repairs were made,
and the school remains in service to this day.

The point, get to the point.

Our first level of obligation is to the public safety, but as with the
Hippocratic oath "First do no harm."  Often older structures don't work
when you run the numbers, but they have stood there for many years
through huge snow drift loads, wind storms, earthquakes, etc..  If it
has not collapsed, it must have found another load path.  I too have
erred on the side of being overly cautious in the past.  But experience
has taught me that if an old building has survived the years, those
pesky little ksi's have found a different way to the ground, and there
is a chance that the system works even for current design loads.  If
not, there is generally time to repair the structure.

I am not advocating hiding your conclusions.  (I have also closed down
structures.)  What I do advocate is that before we "shut em down" we
should:
1.  Do a judicious analysis
2.  Be aware of the consequences of our decisions
3.  Get another opinion.

>From the book of war stories,
Harold Sprague
Black & Veatch
 ----------
From: Lynn Howard
To: seaoc(--nospam--at)seaoc.org
Subject: Re: Ethics 101
Date: Thursday, August 21, 1997 9:57AM

MGriffi119(--nospam--at)aol.com wrote:

> Very Easy. Unqualified YES!!! to all but the shipping scenario. As
> engineers,
> especially structural engineers, our Primary Duty is ALWAYS to
> maintain
> public safety. It would seem not even considerable to say otherwise.
> At a
> minimum, the building official and THE OCCUPANTS should be informed as
> to the
> expected outcome.

I don't want to throw cold water on the idea of structural engineers
running around yelling "the sky is falling" to building department and
building occupants, but you need to be VERY CAREFUL when you issue such
a statement.  Such a statement will probably cause people to take action
(occupants moving out, building dept. closing a building, etc.), and if
it turn out you were WRONG in your declaration, you will be subject to
lawsuits the magnitude of which will be overwhelming.Declaring a
building a hazard should only be done after careful consideration and
analysis.  If you make such a declaration and you turn out to be wrong,
the personal consequences could ruin you.

Lynn