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RE: OMRF (R value) (code development process)

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I can offer some insight into the "smokey-room deals" mentioned by Charlie.

R factors were introduced in the 1988 UBC and were part of a major re-write
of the seismic provisions by SEAOC.  All during this process both the steel
and concrete industries designated individuals to monitor the process and
to attend meetings of the state Seismology Committee.  I was a delegate to
the State Seismology Committee during the development of this code change.

Then and I would believe now, both industries monitored the Code adoption
process at all levels and had representatives who were competent at using
the system to advance their interests.

The proposed code change was a major one and there was a fear that it would
not take much for the building officials to get confused and vote no
because of perceived problems.  As such the Seismology Committee made an
effort to work with all of the stake holders including the various trade
organizations and the structural engineering organizations in the rest of
the western states.  The representatives from the steel and concrete
industries were among the most active and it was perceived that their
support was essential if the code change was to be successful, and as such
several parts of the proposal were moderated in an effort to maintain
support.

There were no formal deals let alone "smokey-room deals" but it was well
understood what the major critical concerns of both the steel and concrete
industries were.  In the case of the concrete industry parity of R factors
was a big deal.  The point is that both industries play the game and are
capable of playing hardball if their interests are threatened.

The code process has always been and I believe continues to be a very
political process. 

AISC appears to have done a lot in recent years to open up the involvement
of different voices in writing the steel code, but I have no doubt that if
the steel code committee went in some direction that threatened the steel
industry that AISC would take steps to correct the problem.

By the way while Henry Degenkolb was still around at the time R factors
were introduced but he was not actively involved in the Seismology
Committee.

With regards to the R factors being "...based upon actual, observed and
tested performance...",  I would suggest that you take that statement with
a grain of salt.  In reality the R factors were calibrated to the arbitrary
K factors that were previously used.  There was some tweaking of specific
values but in most cases the values were more influenced by the opinions of
the delegates than they were by any formal process.  I seem to remember
hearing of a research project by ATC that was supposed to develop a formal
methodology for determining R factors.  The fact that we still do not have
a formal procedure for determining R factors would suggest that all of the
R factors are at some degree subjective.


Mark Gilligan



++++++++++++++++++++++++++++++++++++++++++++++++++++++++=
>ACI is only/purely a technical
>organization and AISC is both a
>technical organization AND the steel
>industry trade organization. 
>As a result, AISC does have more
>sources of revenue that ACI
>(and ASCE and TMS).

But the trade association dues in total are barely enough to cover my
salary. (-:

Scott and I have discussed this at length and don't entirely agree (in a
friendly way, of course). I don't think AISC, ACI, ASCE, etc. are all that
different when you get down to the brass tacks. No one should cry foul
about
income as I do not see the staff starving in any of these organizations.
Actually, one in that list has quite a profit motive in the pricing of
their
publications, conferences, seminars and other products (hint: it isn't mine
or ACI).

Maybe I should just say I don't think AISC, ACI, ASCE, etc. should be all
that different, whether they have a trade association function in-house or
through liaison of similar personnel and volunteers with a parallel
organization. There is no way that any of these organizations would
knowingly compromise public safety to do anything to benefit their defined
interest. I can tell you for my part in ten years at AISC, I have not seen
anyone with a special interest get the special treatment they've sought.
Furthermore, if it ever came to be and I could not successfully prevent it,
I would resign and say publically why I resigned.

In fact, about the only (and the most egregious) place I've seen a special
interest get their way was in the very building code process with which
some
seem to be so enamored. Way back in the days of Henry Degenkolb, R factors
were proposed for the various structural systems based upon actual,
observed
and tested performance and did not treat special moment frames equivalently
across the various materials. Steel special moment frames had demonstrated
better interstory drift capability than concrete special moment frames. As
a
result, steel special moment frames had a correspondingly higher R factor
in
the proposal. However, the political wranglings and smokey-room deals
negated this technical finer point and the final building code adopted the
higher steel R factor for both steel and concrete. Post-Northridge steel
special moment frames still have a demonstrated higher interstory drift
capability than concrete special moment frames. I suppose it does not
really
matter in the end because R factors are all just SWA guesses anyway.

I did not mean the above as an attack on reinforced concrete, ACI or
anyone.

Charlie

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