Engineers love bridges. I think it is because they appear so simple, but engineers appreciate how much thought and calculation are required.

Living in the Bay Area, we have two of the most impressive bridges in the country. It’s a great time to be here because they are currently rebuilding the Bay Bridge, designed to last 150 years and withstand a whopping 8.5 earthquake. Check out this short video showing how awesome it will be:

And for those of you that haven’t seen this famous video of how not to build a bridge:

Nerd note: In engineering classes we were taught that the reason the Tacoma Narrows Bridge collapsed was because the wind provided a periodic frequency that matched the natural frequency of the bridge. (Non-nerd note: think of a parent pushing a child on a swing – the parent (the wind) is providing a periodic push of the child (the bridge), who is moving back and forth at a frequency. If those frequencies match the kid will swing higher and higher.) The real cause was aeroelastic flutter – aerodynamic forces, not periodic wind gusts, that matched the natural frequency of the bridge. There is a startup that created a tiny wind powered generator using this principle.