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Re: 10/Lw Response to Ron Hamburger

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Ron,

Let me respond to your comments by pointing out that Richard Flower posted a
question on the listservice asking specifically what the intent of the 10/Lw
was as applied to wood framed residential structures. This does not excuse
passing along information that may have been inaccurate (not necessarily
incorrect) and I thank you for the clarification. I do suggest you read
Richards post to understand that he and his local building officials are
unclear as to the intent behind the code and how to interpret it as it
applies to wood. My comments were prefaced with a statement to indicate that
I would attempt to explain but that the issues regarding intent where my
opinions (not my exact words but my intended meaning). Richard was not
concerned as to the implication of the code for other than residential
structures. Therefore my comments are opinions (since there was no original
intention of how 10/lw should be applied to wood framed residential
buildings).

I choose to respond the same day he posted his message - Saturday. This is a
"real-time" listservice and some of the participants respond as the message
appears rather than to wait for a response from Seismology or Code
committee. In addition, Richards post was addressed to Stephen Fisher and I.
Therefore, I felt it appropriate to offer my opinions.

I would argue that your comment "None of the above is correct" is in itself
incorrect. It may not have been the original intent of the policy makers,
but it does create the problem that I have explained to Richard.

I do take responsibility and apologize to Dr. Gosh as I was responding from
my memories and not from documents with his name. As I only attended one
seminar and read posts of his position, his name did not instill itself deep
enough in my mind to get it correct. I apologize to Dr. Gosh (as I do
constantly to Nels Roselund for forgetting how to spell his first name and
Nels is a close friend).

As to the issues related to Dick Phillips comments - they are public record
both in the archives of this Listservice and in front of 200 participants
(including John Shipp, Bill Nelson, Bill Warren, Mike and Brian Cochran and
many others on this list) at the ASD/LRFD seminar. If you believe that Dick
is not responsible for setting the limit of the constant at 10 then you need
to take the issue up with him or allow him equal time to refute you.

It does not matter whether the intent was to prevent long walls from being
penalized as you suggest or whether short walls are penalize by application
of this redundancy factor - there is a valid argument from both sides as Dr.
Gosh points out. Rho acts within the code as a multiplier of the horizontal
Load applied to the building. There is a very good chance that Rho will
exceed 1.0 when calculated in a line of shear with walls that are less than
10'-0" in length. The value of Rho can easily exceed 1.5 and (I am not sure
if this is in the code without specifically searching) I know that local
building departments in my area have a standard correction sheet that allows
the engineer to set Rho equal to 1.5 rather than calculate the actual value.
Any way you look at it - the residence is penalized until the Seismology
committee responded to the consternation of the community over this and
other issues that were neglected to be thought out before becoming code.

I think the bigger issue is that it is much easier to create an accurate
code than try to change one after it has been adopted. The published
comments on the Seismology Website are not accepted by some of the local
building officials. One of the List members pointed out that it was not even
accepted by Tim McCormick in Santa Monica (a former List member) as his
position (and that of other building official's) is that the only way it
will be accepted is by code change or publication in Building Standards. The
changes must come from ICBO and to my knowledge, none have to data.
Difficulties still exist in various building departments regardless of the
little effort put in by Seismology to address the communities needs. I don't
understand why there is so much more effort spent arguing the well-intended
efforts of those who participated on the committee rather than taking
responsibility to set a priority that corrects mistakes and accelerates the
commentary and working examples that are needed to do our job?

Your references to Dr. Gosh's interpretation of the importance of not
capping the 10/Lw ratio for structures other than wood is proof that the
flaw existed from the start. Inasmuch as it was not corrected before
becoming codified allows the wrong interpretation to become as valid as the
one Seismology intended. Who is responsible for this and what do you think
needs to be done to correct it?

Please remember that the members on this list were told implicitly that
there would be no revisions or corrections as ICBO's work has, essentially,
been complete and the next project was the IBC. Unfortunately, many of the
same unresolved error are duplicated in the IBC. Do you suggest we sit back
and silently accept what is dished out? I don't think that is the most
responsible thing for a professional engineer to do when it becomes the
price to be paid for the error passes on to the general public.

There are other unresolved issues besides the skewed shearwalls that you
commented on - many issues which are discussed daily on this list. At the
core of all of this is the fact that as of 1:30PM there have been no other
posts responding to Richard from those who should have responded to all of
the communities questions regarding code intent.

Dennis