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RE: STANDARD PRACTICE

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I agree, and this is what is so disturbing. Calculations balance detailing.
In my opinion, one can not be done without the other. While I understand
that the calculations are performed in house but not submitted, there is no
"check" to assure that the calculation has been done. Some years ago
engineers submitted calculations which included the words "by inspection"
meaning that the results are so obvious that the engineer need not submit
the calculations and recognizes that the solution is grossly over
conservative to meet the needs of the design. For example a 6x14 header for
a 16' garage door may be installed and the engineer indicates on the calc's
"By inspection, use 6x16 DF #1 header".
In the last number of years, I have seen this practice fall further to the
wayside. I see more engineers taking the opportunity to verify the numbers.
Most of it was due to the same errors of judgment that said, "By Inspection,
a shearwall with plywood both sides and loaded to the maximum but within the
3.5:1 aspect ratio will deflect within code limits". UNTRUE! Damage occurs,
the engineers butt is on the line, simply because it was considered standard
practice not to design to deflection.

In my opinion, if an engineer takes the time to prepare the analysis for
compliance to the code, it requires only one additional step to submit the
calculations to the building official who, if he is doing a competent job,
will review the analysis to insure that the demands are within the current
code requirements.

Just my opinion.
Dennis

> -----Original Message-----
> From: Christopher Wright [mailto:chrisw(--nospam--at)skypoint.com]
> Sent: Wednesday, June 13, 2001 11:51 AM
> To: SEAOC Newsletter
> Subject: RE: STANDARD PRACTICE
>
>
> >Would you have us believe that formal
> >calculation submittals and plan checks actually lead to better
> engineering
> >practice?  Do you have any proof of that?
>
> I think William LeMessurier's error in the Citicorp wind load analysis
> for the skyscraper design was caught by someone reviewing his original
> design. And I daresay that the deficiency in the Hyatt-Regency skywalks
> would have been caught sooner had the calculations been formalized in a
> report.
>
> Submittals are much more the rule than the exception here on the dark
> side, because they're used in customer design reviews .My own experience
> is that formal submittals make the design intent a good deal more
> apparent. I've also found that simply organizing results for a formal
> submittal is a good check for internal consistency. Building construction
> may be a lot different than mechanical design, but I'd find it damn near
> impossible to review a design for adequacy simply from the drawings--it'd
> take forever, for one thing, and for another, if I did happen to find
> something that didn't fit, it'd take just that much longer to figure out
> who was wrong without the original design basis.
>
> And when I'm doing any testimony where design is an issue, the first
> thing I want to see are calculation summaries so I can determine design
> intent. They're also very helpful is determining whether the designer was
> being systematic or just hipshooting. That said, most of that sort of
> thing mysteriously disappears before a deposition, so I don't get my wish
> very often, but I think a design report is as much a record of the
> designer's intent as drawings. I don't think I'm flattering myself too
> much to say that I can get a pretty good idea of the care taken with a
> design from the records in the engineering file.
>
> Of course I've also seen where a formal submittal really is a lot of
> bureaucratic nonsense. I'm working on one now where machinery trials are
> being held up for lack of a few pieces of paper.
>
> Christopher Wright P.E.    |"They couldn't hit an elephant from
> chrisw(--nospam--at)skypoint.com        | this distance"   (last words of Gen.
> ___________________________| John Sedgwick, Spotsylvania 1864)
> http://www.skypoint.com/~chrisw
>
>
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