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RE: seismology committee

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I do understand this, but my criticism is based on an existing code that was
derived from the Blue Book and written predominantly by the SEAOC Seismology
Committee. My point is more that existing problems from the adoption of the
97 code are not being discussed openly in the community as Martin suggests.
I know of very little open dialog from July of 1999 to the present that
included members of the Seismology Committee and those outside of the
committee. I am not only including the Listservice, but know of many who are
not online and have written many letters to Seismology of their concerns
with the code.

I should be cautious of this next statement because I know that I will be
"flamed for it". At the 1999 SEAOC Convention in Santa Barbara, I was handed
an envelope by one of the board of SEAOSC that contained letters, computer
disks of documents and more from other engineers who had complaints,
suggestions or simply wanted answers about the codes application to wood
framing. I was asked to take the package and see what I could do through
whatever active channel I could take to resolve some of the conflicts. When
I looked in the envelope later, I noticed that many of the letters and
document files on disk were in the original envelope still sealed. They were
never opened or read. This upset me because individual members were writing
to SEAOSC and SEAOC seeking help or offering suggestions and, like our
listservice, were ignored.

When the code writing committees are isolated as they are from the members
it becomes evident that members are led by the decision making process of a
few volunteers and not be representatives voted by the members to represent
their needs. In other words, the members have no power over the organization
they support.

While I may have passed on the large envelop to the appropriate people who I
believed would help, this help never materialized and it became just another
broken promise to correct what was wrong or to help explain.

I don't think the issue is the next code, but what we are going to do about
a rational solution to the existing ambiguities that occur in a code most of
us use daily.

Dennis S. Wish, PE

-----Original Message-----
From: Scott Maxwell [mailto:smaxwell(--nospam--at)]
Sent: Thursday, February 08, 2001 10:18 AM
To: seaint(--nospam--at)
Subject: RE: seismology committee


I won't step into the debate of the use of the term "bashing", but I will
reinforce Martin's point about extend of the "power" of SEAOC's Seismology
committee.   I think that it is unfair to lump all the critizism of the
seismic code at SEAOC's Seismology committee.  From what I understand,
with the advent of the NEHRP provisions and the adoption of those
provisions into the model codes, the SEAOC Seismology has lost much of it
past power.

Keep in mind that in the past the UBC seismic portions WAS the SEAOC Blue
Book.  This is no longer the case with the IBC and was never the case with
the BOCA and SBBC codes.  From my understanding, the seismic code of today
and the future is a product of NEHRP which is a product of the BSSC
committees.  I am sure that at least some of the SEAOC Seismology
committee members are also participants in the BSSC process, especially
since California IS still one of, if not the most, earthquake aware states
in the country.


On Wed, 7 Feb 2001, Structuralist wrote:

> Martin,
> Why is it when criticism is levied, it suddenly becomes bashing? My
> were not to bash any group but to criticize that Seismology has chosen to
> address these issues internally and continues to isolate the members of
> professional community who would like to participate. From your comments
> seems that if a rational exists for Rho, it will be accepted as a buffer
> when the rational is simply impractical.
> You are correct, an envelop solution misses the big picture and penalizes
> not only the structural elements but the clients budget.
> While probability statistics are useful when helping to make a decision,
> NAHB-RC has produced sufficient probability studies that may or may not be
> skewed to their particular bias for Conventional Construction. Who can
> with Statistics - is Hamburger correct or is Jay Crandell correct (or
> respective groups who have produced valid statistical studies).
> "Where are the Bodies?" Frank Lew's famous words that will forever haunt
> The first step is to stop accusing professional practitioners of bashing
> seismology committee and start realizing that what these qualified
> practitioners (verses theorist of statistical studies) must contend with
> the business of structural engineering and the increasingly strong pull
> the other direction (Conventional Construction) that is slowing making
> engineered residences only affordable by the wealthy.
> Enough of us are seeing these changes in the industry and it's time to put
> it all into proper perspective.
> The failing of the Seismology Committee is that they wish to remain
> from those who are not physically able to participate and therefore,
> ignore the concerns of those outside. While each of those studies are
> underway that you mentioned, you might consider that the time to discuss
> this with the practitioners is before you have committed to code.
> Geez, it frustrates me when it becomes so easy to accuse others of bashing
> when in reality the ones who are getting bashed are the practitioners who
> are lost in the use and interpretation of the code. But then again, this
> the reason SEAOC does not need me as a member - I have nothing to offer.
> Respectfully,
> Dennis S. Wish, PE
> -----Original Message-----
> From: Martin W. Johnson [mailto:MWJ(--nospam--at)]
> Sent: Wednesday, February 07, 2001 10:41 AM
> To: seaint(--nospam--at)
> Subject: seismology committee
> Since we seem to have started another round of seismology bashing, I
> I'd
> mention a few things that the committee has been doing;
> We have had discussions about the rho factor.  Clearly it is arcane and
> easily justifiable.  It has curious step functions which cause wide
> variations
> to occur with minor structure changes.  Gary Searer's letter used these
> fuctions to argue his point by showing these exaggerations.  Currently a
> group
> within SEAONC is meeting and having discussions about a possible revamp.
> a
> part of this, Ron Hamburger wrote an interesting paper in which he used
> probabilistic design methods to show that the concept of redundancy has
> validity
> in improving the margin against collapse - in other words, that we should
> not
> necessarily throw the entire concept of redundancy out. It is probably
> to
> take several months for this committee to work something out.
> I have personally pushed for a  code change proposal for the IBC 2002
> supplement
> (and also in ASCE-7, which will be the basis for the NFPA code) to allow
> more
> free use of flexible diaphragm assumptions in light-frame construction
> (i.e.,
> without having to perform an analysis to justify the analysis methodology
> used).
> The down side is that it is going to be within the "simplified method"
> has
> a 25 percent penalty in lateral force.  Personally, I do not like the
> "envelope"
> method of analysis.  In it's pursuit of defining what the maximum force in
> any
> one element might be, it overlooks the big picture, in that the next
> summation
> of base shear is significantly increased relative to what has historically
> seemed to be adequate.  The only justification for the approach is that it
> is a
> way to satisfy a reviewer without more elaborate analysis.  Putting up
> a 25
> percent penalty may actually result in lower base shears than using an
> envelope
> procedure, with significantly less work.
> I have for a year been pushing for the committee to take a fresh look at
> irregularity tables, which also contain curious step functions.  (why is
> that
> special design rules for an in-plane offset of a plywood shear wall
> kick in when the length of offset is equal to the length of wall?  Does a
> foot
> or two really make that much difference?  Certainly the wall holdown
> notice the difference.) Finally that work is getting started.
> We are looking hard at the FEMA 350 documents and developing
> to
> help engineers to interpret their use.  Basically, we are putting the
> engineers
> who developed the SEAOSC document that has been published on their web
> and
> which some engineers have argued as being too conservative, into a room
> some SEAONC engineers, and letting them slug it out.  They are actually
> coming
> to an agreement, thanks to the hard work of Bob Lyons.
> We have held discussions about the possibility of developing some sort of
> small-building design document, that would strip out a lot of the clutter
> that
> is focussed on large or unusual buildings (what I called a "Blue Book
> Lite").
> Probably something will be done about this in the next few years, although
> can't at this time see what can be done about the complexity of the
> materials
> design sections that have been developed and put into the code by AISC,
> AF&PA,
> ACI. etc.  The SEAOC eventual product  probably cannot be presented in the
> form
> of an "alternative code," since building officials only want to adopt and
> enforce a single code, but rather as a subset document that would just
> extract
> out the contents of the current code.  Another model is the old
> Design" document that was published by PCA a number of years ago, which
> presented simple rules-of-thumb equations that could be used to generate
> designs
> that were "about right."
> We have also been doing some more esoteric work such as working with AISC
> develop guidelines for designing BRBF systems, reviewing the findings of
> PRESS test program, and working to develop more rational methods for
> foundation
> seismic design (which is progressing very slowly).
> While there is no end of things to do, there are definite limits on the
> and
> energy of the engineers to pursue them.  Nothing gets done quickly, it
> months to review things and develop a consensus.
> What we have NOT been doing is being a hidden behind-the-scenes dictator
> building codes.  Actually, the seismology committee does not have all that
> much
> power in defining building codes.  The BSSC committees that develop the
> provisions probably have the most influence in that regard, and those
> committees
> are deliberatly balanced between practicing engineers, academicians,
> producers
> and building officials (so much for the "practicing engineers only"
> arguement).
> WIthin SEAOC there has been a movement to move the seismology committee
> from direct code development towards basic science and to find ways to
> more
> closely with national organizations such as BSSC and NCSEA.  Within the
> seismology committee, our code change proposals for the IBC supplement had
> to be
> argued to the NCSEA to gain their support for submittal to the IBC.  So
> there
> was an entire layer of review between us and the code process.  That
> we
> still do a very thorough review and take positions on of code change
> proposals
> developed by other parties as well as the NEHRP draft documents.
> regards,
> Martin