Collapse simulation | Fern Hollow bridge

Road salt was a central factor in this collapse and the impact of the salt is illustrated. The the likely collapse sequence has been animated.

This bridge collapsed in Pittsburgh on Jan 28 at 6:40am. With zero fatalities. Located on Forbes Avenue over the Fern Hollow Creek in Frick Park. The bridge was listed as poor condition on the DOT database. The bridge was built in 1971. Structural steel illustrated.

The steel type on this bridge called Cor-ten rusted intentionally to form a corrosion barrier. The lower parts of the structure rusted away from de-icing salt. A structural brace had snapped off and this is shown in this video.