NC Engineer Explains Instant Bridges, Weighs In On Bridge Collapse
A pedestrian bridge collapsed Thursday at Florida International University in the Miami area, trapping an unknown number of people underneath and injuring multiple people, according to Miami-Dade Fire and Rescue.
The pedestrian bridge is what’s called an “instant bridge.” It was constructed in a few hours Saturday morning using a method called “accelerated bridge construction.”
Dr. Reid Castrodale owns an engineering consulting firm in Concord, North Carolina. He is an advocate for the accelerated bridge construction method – he was part of a webinar series at FIU to inform the community about how to build an ABC bridge there.
“Accelerated bridge construction is simply the use of a number of different strategies to try to build bridges more quickly and have less interruption to the traveling public," Castrodale said.
The bridge built at FIU involved a self-propelled modular transporter—basically a vehicle that can transport large objects. It was assembled off-site and then transported to FIU, where it was installed. According to the North Carolina Department of Transportation, there have not been any bridges built using that method here.
Castrodale said he can’t know for sure what went wrong with the FIU bridge.
“I don’t think that anything having to do with the ABC construction had to do with the failure, of course I don’t know at this point," he said. "Once you get it on its bearings and drive the self-propelled modular transporters away, they’re done and the accelerated part of it is done and it’s finished. It must have been something elsewhere in the system.”
Castrodale said people shouldn’t be concerned about accelerated bridge construction, even after what happened at FIU. He even said he’ll continue to push for these types of bridges in the state, especially where he is in Concord.