Re: [Phys-l] Tacoma Narrows

[Bill Nettles <bnettles@uu.edu>]

I don't have access to the write up that was in the film loop that I had at a previous school, but part of the explanation was that the builders didn't follow the original design.  For cost reasons, the stiffening girders were downgraded which, in effect, reduced the damping constants, allowed more torsional motion and increased the coupling with the transverse mode. I suspect the design engineer didn't know what they did, but I don't know for sure.  I'd love to see the official analysis (those of you with time, search away!); I suspect we'll see that the original would have been adequate, and we physicists would have one less bit of history to show our students.  Of course, without the lesson learned at Tacoma Narrows, some other bridge would have failed.  
Bill

> -----Original Message-----
> From: phys-l-bounces@carnot.physics.buffalo.edu [mailto:phys-l-
> bounces@carnot.physics.buffalo.edu] On Behalf Of Anthony Lapinski
> Sent: Thursday, September 08, 2011 4:32 PM
> To: phys-l@carnot.physics.buffalo.edu
> Subject: [Phys-l] Tacoma Narrows
>
> is the lead story on Yahoo News right now:
>
> http://realestate.yahoo.com/promo/5-shocking-architectural-
> failures.html
>
> Interesting!
>
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