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Re: Effects of the New Code on Wood structures - good or bad?????[Subject Prev][Subject Next][Thread Prev][Thread Next]
- To: seaint(--nospam--at)seaint.org
- Subject: Re: Effects of the New Code on Wood structures - good or bad?????
- From: Charles Greenlaw <cgreenlaw(--nospam--at)speedlink.com>
- Date: Mon, 26 Jul 1999 12:19:56 -0700
Last Friday, 7/23/99, Mark Swingle, SE, replied: >Charles >I never once said that my method of bracketing the shears was an absolute >code requirement, I was simply proposing it as a way to cover all bases. >Everyone is complaining about the complexity and litigation, and going on >and on about diaphragm analyses etc., so I proposed a method where you could >be 100% sure that you would not underdesign any wall according to the code, >without doing anything with the diaphragm. So now you are complaining that >I have simplified something that others were saying was so complicated. .... >Saying that the word "considered" only requires thinking about it and not >acting upon it borders on the ridiculous. The considering is a mathematical >considering, not a fantasy. We consider live loads and dead loads all the >time, and then we act upon it. > >Please reread what I wrote and put it into the context of what we're talking >about. ----------------------- Mark, your later post on Friday, that cites and interprets the original 1959 SEAOC code sections 2312 (e) and (g), makes for a good clarification of your earlier one that I responded to. It is perhaps significant that the original Blue Book avoided using the language terms "rigid" and "flexible" that have since become so vexatious. We are going to hang ourselves with the code language we first get careless about, then let our hallowed committees naively enshrine in code for enforcers and expert accusers to rigidly misinterpret against us. Bill Allen and many others are right in quoting Pogo's twist on Commodore Perry, "We have met the enemy and he is us." Jack Barrish was an ace wordsmith and philosopher in addition to his engineering acumen. He was on the Seismology Committee that produced that original 1959 Blue Book. During the 28 years I knew him, he was a stickler about using the right word for the meaning in every situation. He died earlier this year, and Jack Meehan, a fellow committee member from 1959 and retired Chief SE of what's now DSA/SSS, said approvingly of Barrish at the services, "Jack always said there only needed to be two provisions in the building code. 'Don't design anything that will be unsafe, and don't waste anyone's money.'" I have reread what you wrote, and I have considered your take on what I wrote about the ubiquitous code term "considered", which you might reread. Here's what I follow as a standard in interpreting writings. It is part of a 1987 California state Supreme Court decision, and guides lesser courts and others who interpret law: "[In determining the intent of the Legislature so as to effectuate the purpose of the law] a court must look first to the words of the statute themselves, giving to the language its usual, ordinary import and according significance, if possible, to every word, phrase, and sentence in pursuance of the legislative purpose. A construction making some words surplusage is to be avoided. The words of the statute must be construed in context, keeping in mind the statutory purpose, and statutes or statutory sections relating to the same subject must be harmonized, both internally and with each other, to the extent possible. Where uncertainty exists consideration should be given to the consequences that will flow from a particular interpretation." (Dyna-Med Inc v. Fair Empl. and Housing Comm., 43 Cal.3d 1379; 743 P.2d 1323) By the above method, the preponderance of your Fri posting advocated as code policy use of extreme-limit bracketing for both rigid and flexible, and used that rationale to explain away the interpretation that Lynn said he got from DSA/SSS. But a minor element in it indeed floated the bracketing gambit as merely an escape method when one (as usual) can't accurately calculate shear wall and diaphragm deflections. Harmonizing your points (absent your later-posted clarifications) remains difficult, and I stand by what I posted. As for the meaning of "consider" and its derivatives, note that the Supreme Court also uses this term, and in a way consistent with "its usual, ordinary import", ie, as plain language. Consideration of "the consequences" of a particular interpretation would clearly be a mental exercise for the interpreters, not a data-calculating mandate. But as both of us agree, the mental exercise would have definite purpose toward deciding something relevant to the problem at hand. Engineers in code work carelessly use the word "consider" and its derivatives like it was a specialized "term of art" that has a fixed and known meaning in the profession, like the term "diaphragm". But "consider" is used by engineers in all kinds of contexts, and unlike "diaphragm" it isn't even defined in code. Hence the ordinary, broad dictionary meaning must control. As an example, see 97 UBC Sec 2304.7, which says, "Consideration shall be given in design to the possible effect of cross-grain dimensional changes considered vertically which may occur in [green] lumber." (Note the two different uses here of "consider", one discretionary and the other ministerial.) Now would this first consideration have to be a "mathematical considering" as you put it, or would "thinking about it" and taking action if thought prudent be sufficient? And on what authority does the answer stand? For a short commentary on the distinctly secondary role of calculations in structural engineering (secondary to knowledge, judgment, and understanding) see Berkeley, CA, SE Josh Kardon's case study on a steel frame design in his own locale, in his paper, "The Structural Engineer's Standard of Care" delivered at Case Western in March 1999, at http://ethics.cwru.edu/cases/kardon.html (after 7/99 http://onlineethics.org) The author is completing a doctoral dissertation on this at Cal Berkeley. Excessive demand (by the PE Board's hired "expert") for the accused engineer to have endlessly calculated things in residential remodel jobs figured heavily in the appallingly miscast attempts by the PE Board to revoke CE licenses in two cases that I have been a defense witness and consultant on recently. Residential with its low fee resource and high content of structural imprecision is the main focus of this thread, and is the highest risk type of work for licensing board repercussions. SEAOC committees' failing to accommodate the peculiarities of residential work and utopian SE attitudes toward structural perfection are each major factors worsening this depredation against residential CE and SE practitioners. To save your license, figure on $40,000 out of pocket in defense costs if you win, more if you don't and have to pay the Board's costs and attorney fees as well. Thanks for wading into this controversy and taking the effort and initiative to add to it. Each opinion acts as provocation to bringing more out. Giving the ideas themselves rough treatment means we don't have to be rough on the persons floating them. Charles O. Greenlaw SE Sacramento CA
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