Isn’t this the one that has been torn down recently in Monroeville?
MY dad has done a bunch of tests on a lot of Pittsburgh bridges and he claims that most of our bridges are safe and we shouldn’t worry, however it is the type of construction used that makes them ‘not as reliable’ in the long run… but guys like him will come in run some tests and shut the bridge down years before anything tragic happened. (Which is the goal) Sounded to him like the construction worked forgot that the load of the bridge was resting on the surface of it (i forget what he called it.) So when they started tearing apart the surface it released that hold and lost the bridge.
Disclaimer: He said this Thursday morning and I haven’t seen anything about the bridge since. So I don’t know what happened yet.