Earlier this year, the Francis Scott Key Bridge in the US collapsed after being struck by a large container ship. Six people were killed in the disaster and many around the world were left wondering how such an important piece of infrastructure could collapse in such a catastrophic way.

We investigate in this episode of the Physics World Weekly podcast, which features Erin Bell and Martin Wosnick. They are both engineers at the University of New Hampshire (UNH) and they are in conversation with Physics World’s Margaret Harris.

Bell specializes in the structural design and dynamics of bridges and she explains why the bridge collapsed and talks about what can be done to avoid future catastrophes. Wosnick is an expert in fluid flow and along with Bell, is involved in the UNH Living Bridge Project . They explain how the project has transformed a lift bridge into a living laboratory that investigates, among other things, how a bridge can be used to generate tidal energy.

They also talk about the Atlantic Marine Energy Center, which is developing new ways to extract useful energy from the motions of the oceans.