Return to index: [Subject] [Thread] [Date] [Author]

Liability and the '97 UBC

[Subject Prev][Subject Next][Thread Prev][Thread Next]
         \'\                                                     __________
         / '|                From the Desk             ()_________)       
         \ '/                                                     \ ~~~~~~~ \ 
           \                          of                            \ ~~~~~~  
         (==)                                                     \____~~___\
         (__)                  Dennis S. Wish PE                    

I became concerned by the nature of the thread on Rigid Diaphragm Analysis 
that we have created an issue of liability that could be used by any lawyer 
to institute a suit, which may be friviolous, but can be justified by an 
expert witness because of the lack of compliance to rigid diaphragm analysis 
as noted in the 1994 UBC. It does not matter what the target of the suit is, 
as long as the attorney include the lack of compliance to this methodology.

One engineer advised me that there is a standard of engineering practice that 
is based upon the practice of the majority of engineers in that geographic 
area. However, another engineer with extensive work as an expert witness 
informed me that this is not so. He believes that if the method is prescribed 
in the code, non-conformance for what ever reason is sufficient to support a 
liability claim against the EOR.

If this is true, those engineers in Seismic Zone 3 and 4 may find themselves 
suseptable to greater liability if they ignored rigid diaphragm analysis and 
arbitrarily (or by standard practice) designed using flexible diaphragm 
methods where rigid diaphragm may have otherwise governed.
Again, if this is true, our protect should come in the form of a position 
statement from our professional organization (SEAOC or SEAOSC) which 
justifies the use of flexible diaphragm design for lack of suffient design 
examples or deflection criteria for unblocked, flexible diaphragms.

I believe that we all need to write to the California state chapter of SEA or 
at least to SEAOSC to alert them of our concerns and ask that they protect 
their members by issuing a position statment acknowledging the acceptance for 
flexible diaphragm design for the life of the 94 UBC and related Local Codes.

I would appreciate any comments or suggestions from those who agree, disagree 
or those who have suggestions on how to accomplish this. I am forwarding a 
copy of this email to seaosc(--nospam--at) and seaoc(--nospam--at) 


Dennis S. Wish, PE
Dennis S. Wish PE
Structural Engineering Consultant