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RE: IBC "Oops" (Was Residential Design Discussion)

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Ephraim,
 I will ask you this, do you operate your business and accept imperfection on the basis that you are acting in good faith? There are many more issues in the design of residential structures than simply base shear. If you design your homes using full-compliance methods and following the examples set forth in the ICBO Seismic Design Manual II - in other words an envelope solution, then your claim to practicing with undo harm to your clients is simply a false statement.
Possibly you hand your clients a copy of the drawings and a copy of your structural analysis and warn them not to misplace or lose these precious documents because the next time they need to remodel or sell their home, the next engineer will do harm to the home if he or she does not understand how you distributed the shear from the roof and floor diaphragms. These are serious problems and these are not not resolved.
If you believe that the code allows you to choose between a rigid design and a flexible design based on a deflection analysis of the diaphragm, then you will admit that in most cases, the diaphragm of a home is rigid and you are free to design an open front / soft-story structure. You can recreate Northridge Meadows apartment and justify your design by the interpretation of the code while the building collapses as they did after Northridge and after Whittier Narrows.
You can choose to design by simplified Static methods and boost your base shear up to about 24% of the weight of the structure. If you think this causes no undo harm to your clients, then their pockets are deep and they have money to burn.
 
How can you praise those who arbitrarily decide that one code fits all is appropriate for residential structures without doing their homework.
 
I think I've said enough. I give up and you guys deserve what you get. Personally, I'll stay off this list as I'm sure you, Rick Drake and others would prefer I do. Have fun and enjoy your codes. When you design in my neck of the woods and I receive your plans for review - be prepared to defend your design if it does not meet my interpretation. That's what defective codes are for and be sure to pat the backs of those you praise as you resubmit multiple times until you get it right - to my interpretation of the code.
 
Regards and Salutations.
 
Dennis S. Wish, PE
 -----Original Message-----
From: EphHirsch(--nospam--at)aol.com [mailto:EphHirsch(--nospam--at)aol.com]
Sent: Thursday, October 17, 2002 4:37 PM
To: seaint(--nospam--at)seaint.org
Subject: Re: IBC "Oops" (Was Residential Design Discussion)

In a message dated 10/17/2002 2:06:13 PM Pacific Daylight Time, dennis.wish(--nospam--at)verizon.net writes:


When Rick Drake starts to design residences for a living then I might
pay closer attention to his comments.


You might as well include me in that broadside as well, so "pay attention"-  I too in my practice have "designed residences for a living" and somehow have managed to do so under the strictures, requirements, guidelines, whatever, etc. of the UBC '97 without undue pain to my clients, to the intent of the code and sound engineerinig principles, and to my professional practice and liveliehood.  I agree too well that the "code" (take your pick as to which one, or all) is a very  imperfect  thing under which we must labor, but ad hominum fulminations against individuals who participated in trying to formulate guidelines for puclic safety, no matter how flawed these guidelines might ultimately have proven to be (and that proof has yet to be conclusively established), are becoming very tiresome indeed.  Recognize that the criteria to which you, and perhaps even myself and others, object are currently beyond the control of those who, rightly or wrongly but in good faith, promulgated them.  Even, as quotes from un-lamented past politicians have it, "mistakes were made."   So it is useless in flogging that particular horse - which like the Monty Python Parrot is "ex-" - and energies and ire should be directed elsewhere.

Ephraim G. Hirsch, FSEAOC