JoeyDVivre
New member
- Jun 18, 2026
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What happened here? If this was a terrorist incident, there are huge implications for capital markets. It seems that everyone is dismissing that because Homeland Security says it wasn't terrorists. Huh? I can think of all kinds of ways of taking down a bridge that Homeland Security couldn't find without at least a few days and a few engineers on the scene. They haven't even finished recovering bodies.
I hope this was metal fatigue, aeroelastoic resonance, barge hitting support tower, etc. but if another bridge comes down soon, there's a big problem.
Edit: personal story - In 1977, I went to the national Boy Scout jamboree where they installed all these floating temporary bridges. What became pretty clear was that if everyone marched in unison, the bridge would resonate and you could get really crazy torsional vibrations while someone was singing cadence. So, of course, there was this great irony of trying to be very military, disciplined but walking like drunk sailors on this torsional wave. Being boys, we all thought this was great until one of the bridges rotated so much it threw a troop into the lake (which some of us still thought was great). Anyway, they made us stop marching when we were on the bridges.
Edit2: And for you engineer-types this is a fine example of a self-limiting oscillation. As the bridge started twisting, it became harder and harder to march, thus limiting the impact of the vibrating force.
Edited 2 time(s). Last edit at Thursday, August 2, 2007 at 08:53AM by JoeyDVivre.
I hope this was metal fatigue, aeroelastoic resonance, barge hitting support tower, etc. but if another bridge comes down soon, there's a big problem.
Edit: personal story - In 1977, I went to the national Boy Scout jamboree where they installed all these floating temporary bridges. What became pretty clear was that if everyone marched in unison, the bridge would resonate and you could get really crazy torsional vibrations while someone was singing cadence. So, of course, there was this great irony of trying to be very military, disciplined but walking like drunk sailors on this torsional wave. Being boys, we all thought this was great until one of the bridges rotated so much it threw a troop into the lake (which some of us still thought was great). Anyway, they made us stop marching when we were on the bridges.
Edit2: And for you engineer-types this is a fine example of a self-limiting oscillation. As the bridge started twisting, it became harder and harder to march, thus limiting the impact of the vibrating force.
Edited 2 time(s). Last edit at Thursday, August 2, 2007 at 08:53AM by JoeyDVivre.