RUSTED gusset plates.
I am hearing that this possible area of flawed designed was brought to the NTSB’s attention by the engineering firm hired by the State after the accident. And as the article says, these gusset plates are used in bridges and structures of all kinds and sizes all over the country.
Also pointing to the 100 or so tons of rock dumped on the bridge as part of the construction going on.
Yeeeeeeeeah. That's what makes me nervous about crossing old steel bridges. I don't doubt the design. I doubt the maintenance program.
I wonder what the safe lifespan is for steel bridges, even when properly maintained. Each time the beams and rivets get sandblasted, they have to get smaller and weaker.