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Re: Engineering judgement

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I hope "where we are going" is a defensible position on our judgements.
I am one of the first to jump up and say that our clients are paying for our
experience and judgement (instead of just being a human calculator), we must
have a more rational defense to our judgement than "if one is good, two is
better" mentality. IMO, I think your rationale for the shear wall design is
justified whereas the example of substituting #5s for #4s may not be.

Another point which you bring up is one of my favorites. It's the one about
the contractor telling you that you had "engineered the  house  " 10,000 "
times above code... ".This is a good topic to publish because I am fairly
certain there are (especially) younger engineers out there who may be
intimidated by crusty old contractors at a job site who use this kind of
technique to get the engineer to change his/her design (the old
"over-engineered" attack). First of all, I have yet to meet a residential
contractor who either had an engineering degree or had a licensed engineer
on their staff. When I have gotten the comment something to the effect of
"this job is over-engineered", I respond that he/she is not qualified to
make that statement (that's my "G" rated response, my actual response will
vary depending on how caustic the contractor is). Another comment I have
heard is "I've never had to do this before" to which I respond "Well, you
won't be able to say that anymore".

In summary, I do think we need to use engineering judgement and provide a
design above "minimum standards" (whatever that is) where it is justified.
However, I do think we have a responsibility to the owner in holding
construction costs in line by not arbitrarily inflating construction costs
just to CYA.

Bill Allen
-----Original Message-----
From: HARRISENGR(--nospam--at) <HARRISENGR(--nospam--at)>
To: seaoc(--nospam--at) <seaoc(--nospam--at)>
Date: Tuesday, November 25, 1997 8:31 PM
Subject: Re: CalTrans Screw Up/ engineering judgement

>In a message dated 97-11-25 18:47:13 EST, you write:
><< In your example, if the engineer specified #5s @ 16" when #4s @ 16" are
> adequate, then shame on the engineer especially when the project is being
> paid for with public funds. In this case, the engineer should be held
> accountable. >>
>     I would question the use of the word "adequate". In my opinion, the
>uniform building code ( for example )  may be considered adequate by some
>i consider it as an absolute minimum piece of junk that is permitted to be
>     Take the example of plywood shear wall height to width ratios. If you
>are using 3.5 :1 as allowed by the '94 code , it is adequate. The '97 code
>requires 2:1 which my experience reviewing over 1000 Northridge E.Q.
>houses makes me feel is more appropriate. Therefore when an engineer uses
> experience / Judgement  and decides to use 2:1 ratio now , before the '97
>code is adopted , he may be judged by some to be engineering above
>and should be "held accountable ". Where is engineering judgement?
>      Recently on a hillside ( cliffside ) home i had a contractor say i
>engineered the  house  " 10,000 " times above code... I had followed L.A.
>city hillside guidelines in an area where UBC was " adequate "  ( L.A.
>guidelines not required ).
>     If i am to be held "accountable "  for anything above "adequate " ( in
>addition to below adequate ) i wonder where we are going?
>      Tom Harris, SE
>      Thousand Oaks, CA
>     Tom Harris, SE
>     Thousand Oaks, CA