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RE: Simplified Seismic Design Trends

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We have some clients who only want to beat us down on the price of each item related to building design and construction... lowest geotech fee, lowest SE fee, lowest bid contractor... they won't listen when we explain how spending $10,000 more during the design phase will save $100,000 (just a hypothetical) in construction.  All they care about is how much it costs right now. 
 
We sometimes have small projects or very short design schedules where the actual load applied is less important than just getting it done to meet schedule.  Whether the wind pressure is 22.4 psf or 25 psf is insignificant and whether the seismic force is 78.2 kips or 100 kips is also not so important.  I'm not talking about every project, just some.  When designing such projects of steel, I use the "structural steel systems not specifically designed for seismic resistance". 
 
There are of course times when is it best or necessary to do more detailed design, but not always.  I'd like to see more simplified design info in the codes and standards.  Sometimes it is more beneficial to the client to spend the time thinking how to improve the structures constructability instead of calculating loads and designing members.
 
I remember being so proud of my new 1996 AISI design manual (if you haven't see it, it is 8 1/2"x11" and about 2" thick).  I designed a light-gauge steel member and showed the calcs to my boss for review... he checked with his 1968 edition (it was about 6"x9" and 1/8" thick)... got the exact same size member.  The equations he used were much simpler and easier and quicker to use. 
 

Bruce D. Holcomb, PE - in favor of the KISS principle

 
-----Original Message-----
From: Barry H. Welliver [mailto:barrywelliver2(--nospam--at)earthlink.net]
Sent: Saturday, May 10, 2003 8:28 AM
To: Seaint Listserv
Subject: Simplified Seismic Design Trends

I’m looking for some help in identifying any movements or trends to support a simplification in seismic design. I recognize that we have efforts to that effect in the building code (and they are greatly appreciated by small budgeted projects) and am interested in both participating and encouraging these endeavors.

 

While one mans simple is another’s complex, it does seem to me that the trend in code making is a both/and mentality. It’s wonderful that we have both researchers and practitioners hammering out rules, but I fear we’ve lost the ability to distill what we know and focus on getting the most for our design dollars. Perhaps I’ve developed this sinking feeling based on comparisons between my practice 20+ years ago and today. I’ve been (and continue to be) an ardent supporter of EQ code evolution and think for the most part the directions have been justified. I get frustrated however by the quickly adopted provisions which get universally applied to general building design and then get massaged with additional formulation and exceptions. (EOR = End of Rant)

 

Of late I’ve been coming back to the thought….. if Einstein can boil science down to E=mc2, then surely mere structural engineers can aim toward M=wl2/8.

 

Your comments and suggestions would be appreciated.  

 

Barry H. Welliver