Subject: Re: Performance Based Seismic Design - Is anyone interested?
From: Lynn <lhoward(--nospam--at)silcom.com>
Date: Mon, 07 Jun 1999 13:25:31 -0700
I think the problem is that many design engineers are not really
involved in the
FEMA 273 / 310 evaluation of buildings. While I was aware of these
had a copy of FEMA 273 for reference, we really were not involved to a
in actually using these standards until recently. Our office has had to
get very familiar
with them, and we now use them a lot and have found many of the problems
brought up, as well as many others.
>From what I can tell, these documents are being used more and more now,
will rise as engineers get into them more.
I wish I had time to go to some of these seminars, but I don't. Most
California like ours are very busy and cannot afford to have their
engineers out to these
seminars right now. They need to be in the office trying to make those
> 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
> 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
> 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