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Re: Repair Standards before the next one....-Reply

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Richard Ranous/OES(--nospam--at) wrote:

>>>In many respects I agree with the statements within this post.  (See my
response to Fred Turner).  The problems encountered with the City of
Oakland ordinance is that there was no evaluation criteria.  Consequently,
no problem has been solved.  What one engineer calls a 25% loss of
capacity, another engineer may say is only 10%.  The evaluation is based
solely on judgement.<<<
I will agree that any criteria is subjective and based on judgement.  Oakland's
ordinance has certainly resulted in confusion, but it provides a more rational
basis than a cost basis.  Whose judgement do we trust more, the engineers
calculating capacities or contractors, et al who estimate costs? 

>>>As for ATC-43 this is a good start at arriving at a criteria.  From a
personal standpoint I disagree with the criteria that is being developed.
The intial drafts have taken the approach that the reduction in building
stiffness from cracked elements does not enter into the considerations of
how badly a building has been damaged.  Additionally, I believe that the
criteria on crack evaluation is too liberal.  In all fairness to ATC, they
are taking another look at the draft based on many comments they received
from SEAOSC, SEAOC, the SEAOC seismology committee, and other
I am happy that you agree that ATC 43 is a good start.  As a member of the
panel that developed ATC 43, I am also aware that you are not in agreement
with some of the requirements.  To date however, I am not aware of any
technical inadequacies with any of the provisions put forth by SEAOSC,
SEAOC, the seismology committee, or others.  I am also not aware of any
changes being made to the technical provisions of the document based on
comments by those groups mentioned previously.

>>>The best approah to the problem is to have triggers based on the structural
condition of the building with an evaluation criteria which leads to
consistency from building to building.  Until that approach can be
developed, reviewed, discussed, and adopted, the Appendix Chapter 34
criteria is a good interim standard.<<<
The time to start developing a structural evaluation approach is now.  The
Appendix Chapter 34 needs some improvements before it should be even be
considered an interim standard.  If you would like, I could discuss with you
some of the problems and some suggestions to improve this criteria.

>>>By the way, the repair cost is structural repair only and does not include
nonstructural or finish elements unless they are directly involved with the
structural damage (i.e., need to be removed to reach the structural
While this may be your interpretation of the provisions, the wording could be
interpreted differently.  The "value of repairs required to restore the structural
members to their pre-event condition" can and has been misinterpreted to
include other costs.  The determination of what is required to restore a
structural element to its "pre-event condition" has also resulted in considerable
debate, as you may be aware.

Brian Kehoe