Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: $0.02 worth of LRFD/ASD

[Subject Prev][Subject Next][Thread Prev][Thread Next]

Use the new Metric LRFD Manual from AISC. You can't miss it - the cover is
safety orange. Of course, now you'll have to go back to LRFD!

Bob Shaw

-----Original Message-----
From: DECATOR, DENNIS [mailto:DBDECATOR(--nospam--at)]
Sent: Friday, December 10, 1999 10:10 AM
To: SEA Int'l (E-mail)
Subject: $0.02 worth of LRFD/ASD

RE: Code conflict
Recently there is a NDS LRFD wood code which may be used so you need not
worry about using LRFD one and ASD other.  If the latest codes of each are
used this dilemma is a moot point.

I was "trained" in LRFD in college and did learn ASD in the job place.  ASD
is very easy to learn since it is kind of a "simplified" LRFD.  Sections,
chapters, are similar and equations are similarly located and sometimes look
alike.  The knowledge is readily acquired once in the work force.

ASD is quick and cheap in terms of time to use.  It is excellent for small
platforms and the like.  However, in most large projects where longer spans
(20'+) are used, LRFD will likely result in a cost savings of steel tonnage
especially in composite sections.  The LRFD steel composite section is more
advanced than the one "stuck in 1989".

Eventually, all steel will be LRFD or perhaps a code more similar to the
Eurocode.  However, it will take time.  It took concrete 20-30 years perhaps
to make the transition.  The present senior generation practically refuses
to learn a new steel code but learned USD concrete in college.  Their
predecessors likely only used Working Stress.  Few young engineers are aware
Working Stress Design of concrete ever existed.  It may take awhile, but the
end result will be LRFD RULES.

Besides, the ASD codes will eventually just fall apart from use with no
replacements in sight.

So when can we go to metrics?  I need those units in mm and Pa!!!

Just an opinion.
Happy Holidays!!

Dennis B. Decator P.E.
dbdecator(--nospam--at) <mailto:dbdecator(--nospam--at)>
Harley Ellington Design
Structural Department