Experts say the engineering behind the collapsed FIU bridge in Miami was nothing special.
As scrutiny turns to what led to the bridge’s collapse, the structure’s so-called unconventional engineering and construction has been put in the spotlight, but the techniques used to build the bridge, known in the business under the umbrella term of “ABC” or Accelerated Bridge Construction, are typical and long-standing practices, according to Wired.
ABC refers to a series of techniques that reduces the amount of construction that takes place on the site itself. This means prefabricating elements of the structure elsewhere and then using Self-Propelled Modular Transporter vehicles to move and install the bridge on the site. The ABC method dates back to the 1970s and, though more expensive, is favored due to its comparatively strong track record for keeping workers safe on the job.
About 800 bridges were built with federal funding using the ABC method between 2010 to June 2012, Wired reports.
Civil engineer Michael Culmo (who was not involved in the FIU project) said the collapse requires further investigation beyond the ABC method the team followed.
“The real question is, what was happening at that moment that it went down? Was the contractor doing something on the bridge? It was standing for five days, doing just fine. What happened on the fifth day?” he said to Wired. “Usually, it’s more than one thing that causes a collapse.”
The collapsed FIU bridge was built by FIGG Bridge Engineers Inc. and Munilla Construction Management as part of a $124 million campus expansion, as The Real Deal reported. Days before it collapsed, an engineer involved in the design reported “some cracking” to a state transportation official but said he didn’t view the cracks as a threat to safety.
The National Transportation Safety Board is investigating the collapse, which killed at least six people, and will release an official assessment with their findings. [Wired] — Erin Hudson