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Re[2]: Performance Objectives

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What the authors write sounds a lot like the SEAOC Vision 2000 project.  For 
a 
quick summary, take a look at Appendix B of your 1996 SEAOC Blue Book.  The 
SEAOC Seismology Committee (Code Writers) have developed a framework to 
incorporate different levels of performance.

FEMA also has sponsored work in this area.  FEMA 283 (Free from FEMA) is 
entitled "Performance Based Seismic Design Of Buildings" and was prepared 
with 
project participation by a large number of the SEAOC membership.

Instead of Code Levels "A", "B", and "C", we should think in terms of 
established and defined performance levels such as "Fully operational, 
Operational, Life Safe, and Near Collapse.

The hard work will be writing the actual code language to achieve the 
specified 
/ desired performance level.  There's still a lot of work to do.

Rick Drake, SE
Fluor Daniel

_______________________________________________

Per Bruce Resnick:
     
> Perhaps we could codify structures into A, B, and C levels.
> "C" level would be code minimum as it exists now.  Levels "A" 
> and "B" could represent code increases in lateral design (say 
> 25% or 50% more seismic), and vertical design (higher live
> load and/or deflection criteria).  The advantage to codifying
> this is that the developer/builder/owner could then legitimately 
> increase the value of the property by saying it was built to
> code level "A" or "B" and there would be permits to prove it. 
> Maybe this would also increase the public awareness as to what 
> people are buying.
     
     _______________________________________________________

Per SHERMANWC(--nospam--at)cdm.com

I think such classifications would be great, if we could get the code 
writers to
do it.  The bare minimums could be the default, but a client could require a 

higher classification by contract and "essential" facilities could be code 
required to meet a higher classification.
     
I've been thinking along similar lines that structures should be classified 
according to quality requirements for design.  Higher classification levels 
of structures should have a higher specified level of quality control (such 
as required independent checking of design calculations, independent peer 
review, documentation of interdiscipline cross-checking, etc).  I've been 
thinking that this should be covered in standard contracts for engineering 
services.
     
The purchaser should have the choice of specifying increased levels of 
quality 
control if willing to spend a little more money for design.
     
Currently, I have great difficulty with the lack of definition of quality 
requirements in current standard engineering contracts.  The EJCDC standard 
contract documents only require conformance to the "Standard of Care".  This 
is 
a very loose term and is subject to interpretation.  Unfortunately, I've 
seen 
significant variation in the standard of care in the industry I work in and 
clients do not seem to be given the means to directly control the standard 
of 
care.  The engineering industry needs to work on this.  (I've suggested to a 

couple of members of ACEC that this be addressed.)  Where the purchaser of 
engineering services must make choices, some items may be better addressed 
in 
the contract for services rather than in building codes.