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Performance Based Seismic Design - Is anyone interested?

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Applied Technology Council (ATC) with Building Seismic Safety Council (BSSC) 
has been and will be holding Regional Training Seminars entitled "NEHRP 
Guidelines for the Seismic Rehabilitation of Buildings (FEMA 273) in many US 
cities.  I do not know the exact number of engineers and others who have 
attended these Seminars, but by the time these Seminars are completed, it is 
reasonable to assume that over 1,000 engineers will have attended them.   An 
important part of these Seminars discusses "Performance Based Seismic Design" 
with seismic rehabilitation objectives of "Immediate Occupancy", "Damage 
Control", "Life Safety", "Collapse Prevention", etc.

My concern tonight is whether or not the SEAINT List Server is reaching some 
of these over 1,000 engineers and others, who will have attended these 
ATC/BSSC Seminars.  The fact that they took two days of their valuable time 
to attend these Seminars indicates to me that they represent a group of 
engineers and others who are trying to keep up the latest developments in 
earthquake engineering and SEAINT List Server should be trying to reach them 
because SEAINT would benefit from their input.  

I do not see discussions of FEMA 273, FEMA 310 and similar Performance Based 
Seismic Design guidelines and "prestandards"  posted on the SEAINT List 
Server.

Based on my experience as a "Peer Reviewer" for three case studies in the 
BSSC Case Studies Project,  which applies and tests the FEMA 273 Guidelines 
to real buildings,  at least two out of my three case studies Design firms 
expressed in their case studies reports that they felt that the FEMA 273 
Guidelines methodology would someday be the basis of the seismic building 
code provisions in the United States. 

On June 3, 1999, I posted "And the Buildings Will Not Even Catch a Cold" - 
Performance Based Seismic Design" and on June 5, 1999, I posted "Prescribe 
"Immediate Occupancy" for your FEMA 310 and 273 Evaluations and 
Rehabilitation's and Your Buildings will not even Catch a Cold."  I thought 
that these postings to the SEAINT List Server would attract at least a few 
remarks and thoughtful replies from engineers who are interested in 
Performance Based Seismic Designs.  As of  
nearly midnight on June 6, 1999, NO REPLIES! 

Can SEAINT List Server claim to represent the broad cross-section of the 
structural engineering design profession when there are no discussions of  
other important structural engineering issues on SEAINT?

I have followed FEMA 273 since it conception and served on the FEMA 273, 
Chapter 11, Non-structural, "Architectural, Mechanical, and Electrical 
Components" team, which produced the one Chapter in FEMA 273 that has had the 
fewest critical comments as compared with the other FEMA 273 Chapters.

It will come as no surprise to the members of the SEAINT List Server that I 
have serious concerns about FEMA 273, particularly the inadequate provisions 
in FEMA 273, Section 2.11.4, Overturning.  These inadequate overturning 
provisions in FEMA 273 are "handed down "  to FEMA 310, A Prestandard (what 
ever that means) and the proposed ASCE/FEMA 273, which is now going through 
the ASCE Standards processes. 

In recent months, the SEAINT List Server has been filled with discussions of 
"rigid" vs. "flexible" wood diaphragms and other issues related to the 
interpretation of the 1995 and 1997 Uniform Building Codes, and 1997 NEHRP 
Provisions.

In my judgment, by neglecting to even look at and discuss the obvious 
inadequacies in FEMA 273,  the SEAINT  has been and continues to "look at the 
gnats (small biting flying insects)  while the unherded elephants run by."

If you like the 1997 Uniform Building Code or the 1997 NEHRP Provisions, you 
will love FEMA 273 and FEMA 310.

I will not live to see the FEMA 273 methodology implemented into the future 
building codes.  Maybe by then someone will remember that an old engineer, 
Frank McClure, "sleepless"  in Orinda, CA told us that the "bridge is out and 
the train is coming."

Like medical doctors, prescribe and provide treatment for your buildings to 
recover to "Immediate  Occupancy" health and these buildings will not even 
catch a cold so the FEMA 273 and 310 medical books would have you believe.



Frank E. McClure       FEMCCLURE(--nospam--at)aol.com    June 7, 1999

File: PBSD1.doc