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Mistreatment of Seismology Issues - Part 2

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Below are my closing observations with regard to "Mistreatment of Seismology

On 98-11-25  Rick Ranous wrote: 

"I have listened to this thread with great interest. The question has been
discussed from the standpoint of what engineers need to do from the design
standpoint. Additionally, we have discussed what a design based earthquake is.
All answers have been well presented and raised some key issues-again from the
engineer's standpoint. 

>From my standpoint, I would like to hear now how this information is given to
the general public so they better understand what it means when they are told
their building "is in conformance with the code" (whatever edition that may
be).  Many of my projects relate directly to this concept.  When the firm
evaluates a building and tells the owner they can expect a 25% to 30% loss
from a design based earthquake, they obviously get concerned.  Many will say,
"but the building was built to code!"

also be the first step in addressing the overall question of the engineering
image to the public.  A wonderful task for a public relations committee
(BTW--this could easily be a virtual committee).  ANY COMMENT ON THIS IDEA

Rick Ranous
(formerly OES) now EQE

On 98-10-27 Charles O. Greenlaw, SE, Sacramento, CA wrote:

" ..... In my opinion, far too many rash and overreactive code detail remedies
have been promulgated, almost at knee-jerk fashion, in the Los Angeles area on
the heels of  the emotional shock Northridge caused. But is it hardly
unprecedented.  .... Unlike in the military, where defeated commanders are
replaced with unimpaired once, after Northridge the same officials who allowed
the failed buildings to be built oversaw a great patchwork of remedial code
changes. No reflection on the integrity of those officials, but I think all
those code changes should be regarded as temporary, and replaced by simpler
and more coherent once formulated from a distance and free from control by
those having personal responsibility at the time of disaster. Code needs a
fresh, dispassionate remake, hopefully not (as before) understating the
earthquake shaking or overstating material performance in the as-built
realities. And it needs to be brought back within an ordinary engineer's
ability to grasp and correctly follow". 

MY COMMENTS:  These two statements were the only messages posted on SEAInt
server with regard to seismic code issue suggesting the development of a new
way of defining the measure of seismic design forces in terms of Richter (or
non-Richter) scale magnitude of an earthquake so that structural engineers,
seismologists and general public, by using the same language, can understand
each other. (The owners of structures are also general public). There were no
further suggestions, recommendations or shared thoughts posted on the subject
matter. Thus the topic of great importance (life or death) to 32 million
Californians has vanished in the thin air - probably until another imminent
and inevitable killer-quake wakes us up. 

Since the down-to-earth proposals (quoted above) made by two respected members
of Structural Engineers Association of California were met by total silence
indicating oblivious and far-reaching disregard for the issue on part of the
remaining members of the Association, the excerpt from a speech by a noted
American scientist at commencement exercises at the University of Pennsylvania
delivered over 30 years ago seems to be appropriate at this point in time to
be shared with structural engineers of California:

 "There exist in many parts of the world various species of a sub-family of
ants, the Dolichoderinae, whose individuals characteristically run in trails,
in well established paths, maintaining the same highways throughout many
generations.... These species of ants are essentially blind; they run by
scent; the nest odor is maintained along the trails through the constant
passing to and fro of the hundreds or thousands of members of the colony. The
inherited social habits suffice year after year, generation after generation. 

When a new breed of ants is hatched and passes through its preparatory larval
stages, it is impregnated automatically with the colony odor ... The young
ants become adults, and then, dresses up in caps and gowns or the analogous
vestments of formicine world, they start the endless patrolling to and fro,
saluting each other with twiddling antennae, maintaining the status quo,
keeping alive the social smell that has been established by their forerunners.
... They too go through their training to adulthood, and, with diplomas under
their arms, start out along the well-established path, saluting each fellow in
passing, checking up that he too is conforming to the colony's customs and is
in good odor.

Occasionally, by accident or by some psychic aberration, a trail runner gets
off the beaten path and ventures out alone. Usually he becomes wholly lost or,
after random wanderings, stumbles back onto the good old trail. Occasionally
one of these vagrants is followed by a fellow or two, but the new divergent
trail with its slight and uncertain odors has relatively little appeal. Devoid
of vision these timid adventurers hurriedly smell their way back to the well
scented customs and go on running to and fro, happy apparently to keep clear
of those realms that have not the proper social fragrance.

If a natural calamity disturbs the aromatic trail of the Dolichoderinae,
consternation and helplessness ensue. If a strange insect appears, blind
fighting results - then back to patrolling out and in;  a sudden obstruction
on the path, brief excitement follows, and the trail is reestablished with as
little diversion as possible from the former path, and on they go as before;
... back to the beaten path, no matter how circuitous or absurd it may be,
back to saluting, the twiddling, and the maintenance of the old social aroma".
(ISBN 0-688-01545-X published in 1983 by William Morrow and Company, Inc;
N.Y., N.Y., First Edition, pages 89-90). 

Yank (Ret.)