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Re: 97 Code is a Life Safety Standard

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My understanding (i.e. what I was taught) is that the code is a minimum
"life safety" standard.  That is that the code provides for a minimum
standard to which the building should be designed which will minimize loss
of life.  This goes hand-in-hand with many of the PE/SE statutes (i.e. a PE
is supposed to "safeguard" the safety of the public).  It has been noted
many times that you may design to a stricter criteria that could begin to
minimize damage to buildings and thus reduce economic impact of natural (or
un-natural) disasters.

Having said that, it is MUCH easier to advocate stricter criteria than to
impliment it.  Most owners would think you are nuts to spend two or three
times as much (or more) up front to build a building that would sustain
less damage in an earthquake.  While I think your words are little strong
(i.e. "hide behind 'the Code is a Life Safety Standard'"), I agree that an
owner should be informed of what performance level you are designing to.
But I will bet that most owners either won't grasp the potential future
damage or just won't care.  Utimately, it is the owners decision as to
whether or not they want to spend the extra money now to potentially
minimize future damage.  It is their gamble, granted with potential impact
on the rest of our society.  Our responsibility as engineers is to provide
a building that will minimize loss of life in a natural (or man made)
disaster AND to inform the owner of potential economic impact of said
disaster and ways to minimize that economic impact.

If we start to require stricter codes that will minimize the economic
damage, then I would ask where do you draw the line?  Are you going to
forbide that people build cities and home in potential flood zones (i.e.
coastal regions with hurricane activity or river basins)?  Just think of
all the money that could have been saved if we had told people that you
can't build within 50 miles or so of the North Carolina coast.  I can see
the stones flying at me now if I even were to be remotely serious about
such a proposition.

Heck, we can't even get people to consider paying more to implement better
road construction practices that many European countries use that end up
lasting longer.

Just face the fact that most people in our country don't think long term.

I have heard talk, now and again, about including more criteria to minimize
economic damage of earthquakes and the like.  Usually this talk occurs just
after an earthquake that had a large economic impact, but then dies off
after time.

Scott


At 05:17 PM 9/24/99 -0700, you wrote:
>
> Depends on what the meaning of "is" is!
>
>   This ambiguous language is troubling, since it seems to have been
>crafted to kind of
>alert the unsuspecting consumer and the public that the code presumes
>"damage" in
>earthquakes as part of the strategy of absorbing energy.  It also seems an
>attempt to
>limit liability.
>
>   If you compare all the "purpose" statements over the years, including
>the "Blue
>Book's" language on what was expected to happen in the undefined minor,
>major,
>and largest possilble earthquakes, you'll be even more confused.  If you
>want a
>purely Life Safety Code, then we should be taking out the drift limits that
>were put
>in to limit damage and provide occupant comfort in high rise buildings.
>Would you
>want every building in Turkey and Taiwan and Kobe and Northridge totally
>unusable
>and unoccupiable after an earthquake, as long as life loss was minimized?
>
>   As the profession that designs and builds all of the structures that
>kill people in
>earthquakes, wreck the economic basis of business continuity, and devastate
>second
>only to war the connections and relationships we cherish as human beings,
>don't we
>have some professional responsibility to say WHAT the standard should be?
>What
>do we want the outcome to be after the earthquake?  Like for the building
>owner of a
>brand-new steel moment frame in Northridge?  Like for an apartment dweller
>in a
>nonductile concrete building in Turkey?
>
>   Professionally, if we are going to hide behind "the Code is a Life
>Safety Standard",
>then we should fully disclose to the people paying us that their building
>or their dream
>home will be a total economic loss to them and we highly recommend it.
>
>   "Anyone can design a building to withstand the earthquake; it takes a
>Building Code
>to design one that will just barely stand up!"
>
>James Bela
>Oregon Earthquake Awareness / The Quake Northwest
>
>