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Re: Architects Doing Engineering -Enough

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In a message dated 98-05-22 10:29:35 EDT, shahkarp(--nospam--at)sums.ac.ir write:

 
> ..this sort of mentality is dangerous. Yes I'm also living in a non
engineered 
> house with no apparent damage, BUT   I've also seen damage done 
> by a full scale earthquake. If any one reads the EEFIT report on the
> 1990 earthquake in Iran (7.3 - 7.7 on the Richter scale ) will clearly get 
> the point. out of a small city only three structures where still standing.
Many 
> of the demolished structures where less than 10 years old and a clear 
> majority of the buildings where built with good quality construction
material. 
> Lack of structural knowledge or poor workmanship on part of the builders 
> resulted in a tragedy. The same applies to the Armenian earthquake.
> The whole concept of earthquake engineering is not to end up as a statistic.

I've chased my share of earthquakes, starting with Anchorage, and fully
appreciate the damage that a 7+ event can cause.  But in the U.S., the notable
failures we've observed and seen photos of, even when combined with the
buildings that sustained moderate damage but were not noted in publications or
recorded in statistics, comprise a *small* percentage of the building stock.
The number of wood frame houses that sustained the classic failures of cripple
wall buckling, shifting off foundations, and excessive deflections from
torsional racking, comprise an even smaller percentage of the housing stock.

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.

Now, I'll mount the soapbox for a moment.  Compliance with codes and
regulations incur costs as well as provide benefits to society.  The public
has to perceive a reasonable cost-benefit ratio before there is support for a
law or regulation, or for calls for such laws and regulations.  Regarding
seismic performance of wood frame houses, the vast majority of citizens:  1)
have never experienced a major seismic event;  2) have never suffered any
earthquake damage to their own houses;  and 3) don't know of friends and
family members whose houses have been damaged by earthquakes.   So, when folks
on this listserv mount soap boxes to preach ever-stricter seismic design and
construction requirements and practices, and to bash incompetent designers
(i.e. architects and civil-civils), it isn't surprising that they make little
impact on the average citizen, construction mechanics, contractors and
developers.  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.
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.

Bill Allen observed that many postings on this listserv are "preaching to the
choir".  How true.  And equally as effective, since the majority of people
aren't regular churchgoers.

Frank Lew, SE
Orinda, CA