Notes on life, art, photography and technology, by a Danish bohemian and ne'er-do-well.
"They mostly come at night. Mostly."
Monday, March 22, 2010
You may have seen this astonishing footage of the swaying and collapse of the Tacoma Bridge in 1940. The problem was that in the wind storm it went into resonance with it's own speed of vibration, so it went into feedback and and the swaying got stronger and stronger. It collapsed like a wine glass in the right musical note.
What amazes me, though, is that even under this tremendous swaying, the bridge still held out for over an hour! That's some strong sh*t there.
I'm always amazed by that footage. I studied aerodynamics in college and love the physics involved with the collapse. I especially find it interesting how the bridge motion was primarily twisting, not side-to-site or up-and-down as can been seen by watching the centerline of the road at about 2:10 in the video. It's also good to remember that bridge designs changed considerably after the collapse to prevent it from happening again.
Yes, they have to do something to change the "note" of the bridge, like holding down a guitar string.