Jan
15
Written by:
Russ Henke
1/15/2008 11:47 AM
Our family is planning a modest addition to our relatively small house in California. We plan to utilize internal steel beams similar to those uniquely used in the existing house, built in 1995. We believe the steel cage created by these beams adds seismic stability. However, during the recent planning for the addition, we discovered that the building code in our city has changed since 1995. The steel gussets used where multiple beams are joined must now be designed per a newly adopted code with far stricter strength standards than before.
We are gratified that the building code now has these stricter requirements, even though the CAD software used to design the original steel gussets in 1995 is identical to the CAD software used now.
Because the design of our modest steel cage is no better than the skill and up-to-date code knowledge of the engineer/architect using the CAD software. It has always been thus –
CAD software, old or new, is no substitute for the experience and savvy of the person wielding the tool.The lesson came home to us all again on January 15, 2008, when the
National Transportation Safety Board revealed that investigators apparently found a design flaw in the
collapsed 35W Minneapolis bridge's gusset plates, which are the steel plates that tie steel bridge beams together.
2 comment(s) so far...
Re: Gusset Plates
Wouldn't it be nice if the local building departments had a BIM model of all the buildings under its jurisdiction? In this fantasy future, the department could continuously identify all buildings at risk (and where within the building) as it evolves its understanding of what should be required.
By Brad Holtz on
1/17/2008 1:54 PM
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Re: Gusset Plates, BIM, etc.
BIM models would be great, but today I would settle for the deteriorating US infrastructure to be addressed. For example, a report released January 15, 2008 by the National Surface Transportation Policy and Revenue Study Commission calls for at least $225 billion to be invested EVERY YEAR for the next 50 years to upgrade the nation’s existing transportation system "to a state of good repair and create a more advanced surface transportation system to sustain and ensure strong economic growth." Currently, the US invests far less than that recommended amount. Where would the money come from?
Well, $150 billion a year would be available just by ending the IRAQ war! And since the US economy is again spiraling into the second recession within seven years, a modern FDR-like WPA program would fix US infrastructure and provide much needed US employment.
By Russ Henke on
2/12/2008 9:41 AM
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