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Re: Architects Doing Engineering -Enough

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FLew98 wrote:

> This thread started with a focus on 'conventional framing' requirements in the
> model codes in the United States.  I attended presentations on the Armenian
> and Iranian earthquakes, as well as read recon reports from EERI, etc.  The
> impression I have is that the designs, materials, and construction practices
> for houses in those regions are quite different from those for conventional
> framing in the U.S., and it is not valid to make extrapolations of potential
> damage in the U.S. based on those events.

The first point  is completely correct. Buildings in this part of the world are
built in a different way and  have a considerably  higher mass. But if you
consider traditional Japanese buildings, which as far as I know were built with
wooden frames, you may find a similarity . The famous Tokyo earthquake (1926?) is
a good example that this type of construction has its own problems. More damage
was done in the secondary fire than in the initial earthquake. You also mentioned
fire as a more likely threat. I know one  may argue that there are considerable
differences between the  technologies and particularly urban development patterns
used in each case ( notably less density in the average US suburb ). But I still
have the impression that the risk is still considerable.

Regardless of where you are or which type of construction technology & materials
you use, I believe that the extra cost of making the structure earthquake safe is
a small fraction of the total construction cost plus value of contents in a
average house. Not to mention the value of human life.

> Such apocalytic warnings just don't correlate with their own life
> experiences, notwithstanding the frenzied media coverage of damage after each
> earthquake.  People intuitively know that earthquake risks to their own body
> and property are much smaller than other risks they face and accept.

As engineers our job is to recognize and address potential hazards in our own
field of work. To buckle under public pressure and give them what is not
technically justifiable is not correct. The same people will not hesitate in
taking us to court when something goes wrong.

> Earthquakes have caused fewer than 3,000 deaths in the U.S. in the entire 20th
> century.  Contrast that with the *annual * vehicle deaths of 40,000+, and fire
> deaths of 20,000+.  Yet, people aren't clamoring for laws to require us to
> only drive Humvees at 15 mph speed limit, or to live in concrete bunkers and
> use bedding and furniture made of non-combustible materials.

This line of reasoning can also be used to justify easier laws un traffic offenses
like drink driving. Just compare the total traffic fatalities around the world
with the people killed in wars this century  (I think just W.W.II is enough). I
think you agree that this logic is not applicable. Any step must be taken to
reduce the potential risk.

Sassan Parhizgari, SE
Shiraz, Iran