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RE: OMRF (R value)

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Charlie Carter wrote:

. > I will say, though, that I completely agree with this change because the
. > Building Code "floor" is not the place to be making changes to structural
. > provisions. Humbly speaking, I do believe AISC, ACI, TMS, AF&PA, ASCE, 
. > etc, who write the steel, concrete, masonry, wood, load, etc., 
. > respectively, documents, do offer the correct place for such 
. > modifications. You may not agree, but IBC and NFPA apparently do.

ICBO used to say that they didn't write the building codes; they just 
published them.  The only time that I can remember when a code change 
proposal was submitted by ICBO was when it was an emergency, e.g., wood 
tension stresses, prescriptive welded frame construction.

The people that "wrote the code," according to ICBO, were the people "out 
there," the building officials, trade associations, practicing architects and 
engineers, contractors, professional associations, even janitors or cleaning 
women, who could submit code change proposals for consideration.

These code change proposals, for *all* parts of the UBC were to be submitted 
by a specific date each year, heard by the code committee to which assigned 
at a certain date, and voted on by the Class A members at the annual meeting 
each year.

All code change proposals were to be submitted in the same format.

In the associations that Charlie mentions, I can't recall once seeing a code 
change proposal form that anyone could submit, nor do I recall seeing annual 
published dates where code changes could be submitted.  It always appeared 
that code changes appeared from the associations' code committees, and how 
they got there is anybody's guess.  ACI does publish their proposed code 
changes for discussion in one of their journals, sometimes in ACI 
International, sometimes in the Structural Journal, and sometimes in the 
Materials Journal.

Now, if I understand Charlie Carter's position correctly, proposed code 
changes will have to be submitted to the group publishing (writing) the code 
at some unknown date, and to make sure that it gets in the code, also submit 
it at some different date to the ICC.

Code changes published by associations are not always safe, viz., the 
increase in the concrete shear stress that led to the Wright-Patterson AFB 
hangers, and in wood construction, the sudden increase from 25 percent to 75 
percent in connection capacity with steel side plates, both of which were 
found to be seriously non-conservative.

Whether the code bodies like it or not, different regions of the country have 
different concerns.  Seismic design requirements should not be dictated by 
the area of the country that is not as seismically active as the western 
region of the country.  Likewise, areas of the country subject to hurricanes 
should not have their design requirements dictated by non-hurricane regions.

The only true test of design requirements is conducted by Mother Nature.  And 
Mother Nature will test whether the seismic design provisions of the 97 UBC 
are better than the design provisions of the 94 (and previous) UBC, and 
whether the NEHRP design provisions are better than or worse than the UBC 
provisions.

A. Roger Turk, P.E.(Structural)
Tucson, Arizona

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