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!997 FEMA 273 Guidelines Overturning Problems

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There was a meeting of the ASCE/FEMA 273 Prestandard ASCE Standards Committee 
on February 14 -15, 2000 in San Francisco, CA.  At this meeting were 
presented so-called "Global Issues."   One of the Global Issues was the 
problem how 1997 FEMA 273 attempts to deal with overturning, which was 
highlighted as one of the technical inadequacies in the 1997 FEMA 273 
Guidelines in the BSSC Case Studies Report, now FEMA 343, page 89.

This Global Issue, 2-1, dealing with the overturning problem, is still 
"unresolved" as of the end of the meeting and probably will remain 
"unresolved" pending the results of the "basic research," which is currently 
not funded.  In other words, the ASCE/FEMA 273 Prestandard will not present a 
solution to the FEMA 273 overturning problem, except to increase the Rot 
factors in the "side-bar" equation in the 1997 FEMA 273 provisions. How can 
ASCE promulgate an ASCE Standard for the Seismic Rehabilitation of Buildings 
when one of the most fundamental issue (how to address the calculation of the 
overturning forces at the bottom of the superstructure at the top of the 
reinforced concrete foundation system and at the foundation-soil interface) 
will be "unresolved" because of the lack of the results of the "basic 
research" needed to resolve this important issue?

I have submitted my three case study calculations presenting the FEMA 273 
overturning problem to dozens of knowledgeable structural engineers.  Only a 
few have responded.  One was a retired professor from San Jose State 
University who said that my calculations look "OK " and illustrated that 
there was a problem of how 1997 FEMA 273 attempts to address the overturning 
problem.  Another author of the 1997 FEMA 273 Guidelines wrote me: " .your 
calculations show that the Linear Static Provisions overturning provisions in 
FEMA 273 are confusing and unmeaningful."

Two other structural engineers sent me email messages teling me that my 
calculations show that there were three possible and logical solutions on how 
to calculate the reactions at the bottom of the superstructure to the 
reinforced concrete foundations and none of them were correct.  And finally, 
a respected member of the FEMA 273 team wrote me: "We all (the FEMA 273 team) 
agree with you that the FEMA 273 overturning checks are all screwed up.  AND 
WE DO NOT KNOW WHAT TO DO ABOUT IT."  (Emphasis added.)

I will not add further editorial comment except to say that the earthquake 
engineering profession has a responsibility to provide the best information 
to the public and the profession on how to address the earthquake risk 
problem and to help other professionals in the field who request help.  I 
have sent out dozens of copies of my three case studies calculations and 
asked for comments and help how to address the FEMA 273 overturning 
provisions and except for the above brief replies by the five structural 
engineers, I have basically received NOTHING.  How can we call the earthquake 
engineering profession a profession when it will not help other professionals 
address the problems related to earthquake engineering by providing peer 
review comments and responses for request for assistance to help resolve 
carefully prepared and respectfully presented questions and problems?   Think 
of where the medical profession would be today if they did not function as a 
profession and help other medical professionals who request assistance and 
peer review comments.

Frank E. McClure   February 21, 2000