Re: Midterm Question - Sort of

["Spagna Jr., George" <gspagna@RMC.EDU>]

Ludwik wrote:



-----Original Message-----
From: Ludwik Kowalski [mailto:KowalskiL@MAIL.MONTCLAIR.EDU]
Sent: Wednesday, July 07, 1999 1:18 PM
To: PHYS-L@LISTS.NAU.EDU
Subject: Re: Midterm Question - Sort of


That is new to me (see below). I remember reading that wind gusts
nearly matched the natural frequency of the structure.
Ludwik Kowalski

Leigh Palmer wrote:.

> On a related topic: It always bothers me when the Tacoma
> Narrows Bridge collapse is cited as an example of resonance.
> It's not. The wind was steady, more or less, and there was
> no significant component at the bridge's resonant frequency.
> It is a case of nearly pure DC excitation.

If I may, it's not the wind gust frequency, but the frequency at which
vortices in the downstream side were shed which nearly matched the bridge's
resonant frequency.

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George Spagna
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