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Below are the excerpts from the Internet structural engineering discussion 
group showing how confused are the engineers licensed by the State of 
California (who are supposed to design seismically safe structures) about 
seismic code requirements: 

Mr. F.C. writes re New Code provision: 
I have to echo Roger's sentiments on the IBC (International Building Code, a 
proposed new code).  I got a copy of the "Final Draft" of the IBC. I am 
reluctant to read any document that I can't lift. From the comments I'm 
seeing on UBC '97 (Uniform Building Code) seismic provisions, I wonder if 
anyone can "get it right" 
(It is interesting to note that building officials proposing this new code 
call it "An International Building Code" in spite of the fact that the code 
can be used ONLY in the United States of America !!!)

Mr. R.T. writes re New Code provisions:  
I am serving on the Tucson/Pima County Building Code Review Committee and we 
have been studying the proposed changes........ I am glad that you also noted 
that I included the 1997 UBC as being a "bad" code as the changes were 
massive and only one code development committee meeting was held between the 
adoption of the 1994 UBC and the adoption of the 1997 UBC.  Very little 
opportunity to pick up problems in the changes that were proposed. STOP IBC 

Mr. C.G. writes re New Code provisions:  
There is excessive and unnecessary complexity added in each successive 
edition of (seismic) code, there is increasing and unresolved ambiguity, and 
there appears to be an ever-growing hasty, remote, cocksure and yet 
unvalidated nature to the deliberations. ..... Engineers whose small jobs -- 
residential and storefront commercial -- are ensnared in the tangled web of 
obtuse code provisions that mis-fit the situation...

Mr. J.L. writes: 
..... Another clarification,  diaphragms are no longer listed under the table 
of "elements of structures" (UBC Table 16-O), but have there own independent 
section 1633.2.9.  Unfortunately, rho is not clearly defined for the design 
of diaphragms.  From my discussions with several of those associated with 
"officially" interpreting the 1997 UBC, rho is supposed to be 1.0 for 
diaphragm elements of the structure.  Don't quote me but pray it's true. 
Chasing down the correct interpretation of portions of the 1997 UBC has been 
tricky for me and a wild ride to say the least.  Stay tuned and hold on! 

Mr.R.R. writes: 
I have listened (to this subject) with great interest.... From my standpoint, 
I would like to hear how this information is given to the public so they 
understand what it means when they are told their building "is in conformance 
with the code" (whatever edition that may be). Many of my projects relate 
directly to this concept. When the firm evaluates a building and tells the 
owner they can expect a 25% to 30% loss from a design based earthquake, they 
obviously get concerned. Many will say, "but the building was built to the 

Mr. P.Q. writes: ...... 
This issue is of importance to structural engineers. If we just design per 
code as if it were a cook book, we are going to make mistakes. We should at 
least try to understand the intent of the code......

Mr. C.R.G. writes: 
In my opinion, far too many rush and overreactive code details remedies have 
been promulgated almost at knee-jerk fashion .... Code need a fresh, 
dispassionate remake, hopefully not (as before) understating the earthquake 
shaking or overstating material performance in the as-built realities. The 
code needs to be brought back within an ordinary engineer's ability to grasp 
and correctly follow....

Mr. S.I. writes: 
I am wondering if I interpret 97 code correctly. I have an existing masonry 
bearing wall building with an arched wood roof. The footprint of the building 
is 100ft X 100ft.  The building is a single story and it has on open front, 
solid back wall and 20ft long and 80 ft long walls respectively on either 
side. When calculating seismic forces using 97 code, it is seems like that 
the use of the redundancy factor shall penalize this kind of building for 
having an unbraced front side. The calculations for the redundancy factor do 
not make much sense though. According to the code, r max factor for the 
direction parallel to the open front is equal to the shear in the most 
heavily loaded wall (say 66 kips in my case) multiplied by 10 and divided by 
length of the wall and divided by total story shear(same 66 kips).  So I get 
10/100 = 0.1 and redundancy factor = 0 < 1.  So use p = 1. ----> No penalty 
for a faulty design!

That's why, with due respect to their knowledge and experience, "the 
structural engineers do not understand what they are doing" ONLY  because the 
seismic code they have to follow is the most BLUNDERED engineering code in 
the country. 
Does anyone care to comment ????