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Re: Reliabilitiy - Redundancy Factor, 1997 UBC, Section 1630

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Christopher Wright, P. E. in his November 27, 1999, email message to the 
SEAOSC List Service wrote: "According to Ron Hamburger, code provisions are 
necessarily subject to public review and comment.  Did such review take 
place?  If so what was the result?  If not why not?  Seems like there's two 
versions of this floating around."

Based on personal knowledge, I would like to respond to the questions raised 
by Christopher Wright in his November 27, 1999, email message.

On November 27, 1995, (yes, 1995), I wrote a letter to Robert Bachman, Past 
Chair of the SEAOC Seismology Committee, in response to his request that I 
review and comment on the October 25, 1995, draft of the proposed 1997 UBC 
Seismic Provisions.  I commented that I had concerns about the Reliability - 
Redundancy Factor, how it was defined and applied.  I also wrote that I 
thought the proposed 1997 UBC Seismic Provisions were too complex and would 
be difficult for the average competent structural engineer to understand and 
follow.   I do not recall ever getting a reply to my letter.

On January 8, 1996, (yes, 1996), I wrote a letter to David Bonneville, Chair 
of the SEAOC Seismology Committee, in response to his December 20, 1995, 
letter requesting that I review and comment on the December 1995 draft of the 
proposed 1997 UBC Seismic Provisions.  My letter was six pages long and 
included 12  8 1/2" x 11" hand written calculations to support the statements 
in the type written letter. 

In the Closing to my letter, I wrote: "Limitations on my time preclude 
additional study of Section 1645.1 (now Section 1630 in 1997 UBC) and 
Equation (45-3), (now Equation (30-3) in 1997 UBC).  I sincerely hope you and 
the Seismology Committee will critically review the basis for my calculations 
was well as the calculations themselves and tell me where I am possibly 
wrong.  Based on my calculations and sketches, it appears to me that Equation 
(45-3), as now written, could be counter-productive to providing 
"Reliability" and "Redundancy" in the seismic design solutions that could 
result from the application of the proposed SEAOC Strength Design Code 
Change.  I would encourage the individual members of the Seismology Committee 
to prepare their own similar parametric study type calculations to verify for 
themselves the viability of Equation (45-3) and the wording of Section 
1645.1. If you have any questions concerning any of the calculations or 
statements in this letter or desire additional information, please contact 

I sent copies of my January 8, 1996, letter to Dominic Campi and Tom Hale, 
who I believe were members of the SEAOC Seismology Committee.

The only response I received, was not from David Bonneville, but from one of 
the members of the SEAOC Seismology Committee, who scrolled across a copy of 
my January 8, 1999, letter with a broad felt-tipped pen the wording to the 
effect: "If you use a rho factor = 1.5, you can do anything."  After going to 
all the trouble to prepare 12 pages of calculations and a six page letter and 
then to get such a terse and unprofessional reply, you can judge for 
yourselves about the validity of the public review and comment process that 
Ron Hamburger referred to in his November 27, 1999, email message to the 
SEAOSC List Service on the subject "Committee on Wood." 

If you do not show up at the critical SEAOC Seismology meetings or any other 
similar code committee meetings and present your positions in person, it is 
my humble opinion, you are just wasting your time to simply submit your 
comments in writing.  Based on my experience with attempting to comment in 
writing about the proposed 1997 UBC seismic provisions and the FEMA 273 and 
ASCE/FEMA 273 and 310 proposed standards, unless you show up at the critical 
meetings, if invited, the so called "public review and comment" procedures 
are not very effective in the changing the outcome of the code process 
because the committee members have already made up their minds.

Please understand I get no joy in writing the above email message, because it 
will diminish and abrade the close personal relationships I have enjoyed in 
the past with the people mentioned in this email message for whom I have the 
highest personal and professional regard.

Frank E. McClure    November 28, 1999