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Firm Sued Over Fractures in Steel Frames in Quake

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Ron Hamburger,

Thank you for your  January 30, 1997 reply to my subject email message first
posted on January 29, 1997.

In your January 30, 1997 reply you wrote: "Reports from this research have
been consistently and objectively reported by SAC and included in our various
guideline and advisory documents."

At the end of a SAC Seminar on Interim Guidelines for the Evaluation, Repair
and Design of Steel Moment Frame Structures held at the Fairmont Hotel, San
Francisco, California on October 12, 1995, where you and others made some
excellent presentations accompanied by excellent notes, I asked the Panel the
following question: Why did not the FEMA 267, August 1995, "Interim
Guidelines: Evaluation, Repair, Modification and Design of Welded Steel
Moment Frame Structures", Chapter 12 , References (which covered five pages)
include the important reference to "Seismic Provisions for Structural Steel
Buildings", American Institute of Steel Constructions, June 15, 1992?

As I recall there was a long silence and you replied that the above AISC
Sucommittee report was referenced in the 1994 NEHRP Provisions.  I believe I
responded to the effect that the above AISC Subommittee report would be
helpful to engineers who were being sued and their attorneys because it would
help establish what could be considered to be the "Standard of Practice" AT
THE TIME the engineers designed their welded steel frame buildings.
 Particular attention is drawn to the figures that are presented in the AISC
Subcommittee report some of which appear to be very similar to the
"Northridge welded steel connections."

I understand that the AISC will probably not consider the above AISC
Subcommittee Report in the same light as the AISC "Code of Standard Practice
for Steel Buildings and Bridges", June 1992 and previous editions, as a
"Standard of Practice."  I also realize the above AISC Subcommitteee Report
has many disclaimers in the "Preface" one of which states: "Anyone making use
of this information assumes all liability arising from such use."  However,
considering the professional status and outstanding reputations of the
members of this AISC Subcommittee that prepared the above AISC Report,  other
structural engineers, particularly engineers in small structural firms, would
not have the financial resources to carry out the independent research
necessary to make their own determinations concerning the recommendations in
the above AISC Report and therefore, it would be reasonable for these
engineers to rely on the recommendations in this Report.  The daunting
question remains, why did the AISC publish the AISC Subcommittee Report if it
did not expect structural engineers to use and follow the recommendations in
this Report?  I do not have a copy, but I believe that the recommendations in
the AISC Subcomittee Report were incorporated, in part, in the AISC, Load and
Resistance Factor Design Specifications for Structural Steel Buildings,
December 1, 1993.  

I realize that the AISC has distanced itself from the above AISC Subcommittee
Report  in their "AISC Northridge Technical Bulletin No. 2, October 1994,
page 4, "Recommendation: Suspended the use of details similar to those
prescribed in Section 8.2c of AISC Seismic Provisions for Structural Steel
Buildings consistend with recent actions taken by the ICBO in the deletion of
this prescriptive detail from the 1994 UBC."   I have no problem with the
AISC's Recommendation to suspend the use of details similar to those
prescribed in the above  AISC Subcommittee Report. 

My concern is why such an important reference - the AISC "Seismic Provisions
for Structural Steel Buildings", June 15, 1992 -, which could be very helpful
to engineers to answer plaintiff attorney's questions was omitted from such
an important FEMA 267 Report.

I raise this issue again to the SAC Management, for whom I have the highest
personal and professional regard, to encourage them that all reports (warts
and all)
be referenced in the future SAC publications to serve as a "history" and
important background information for those engineers and attorneys who are
attempting to understand what was the "Standard of Practice" that might have
lead up to the problems related to the Northridge welded steel frame
buildings. 

It would seem reasonable to expect that in FEMA 267. Chapter 12,  References
and in future SAC/FEMA documents that there would be room for the important
AISC Subcommittee Report, "Seismic Provisions for Structural Steel
Buildings", June 15, 1992.

Frank E. McClure   FEMCCLURE(--nospam--at)aol.com       January 31, 1997.