Corolinth wrote:
That's an interesting article, although they give the wrong impression of what happened to the Minnesota bridge in 2007. The gusset plate that cracked wasn't "too thin," it was just never designed for the loads it ended up carrying forty years later. The state of Minnesota overloaded that bridge.
In a general sense, I think this applies to most of the bridge infrastructure in the US (rail, vehicle, etc..).
Technology has made the things that cross these bridges bigger, faster, and heavier, and far more numerous, which coupled with a better understanding of engineering and design, and higher expectations for the government making us all feel safe, makes all of this stuff look like a pile of crap that we shouldn't be exposing our children too. When they were made, they were pretty outstanding structures.
The fact that it was still in fairly good condition at it's age is a testament at how well it was built at the time.