Dive Brief:

• The Miami Herald has reportedly obtained documents from Florida International University through a public records request that indicate cracks were observed in a newly installed campus pedestrian bridge two weeks before its deadly collapse.
• Photographs and an internal email that had initially been unintentionally released, according to the Herald, revealed that project officials detected cracks at the base of a diagonal support member on Feb. 28, 10 days prior to installation and 15 days before the bridge fell, crushing vehicles and killing six people. The cracks were reportedly located at the spot where the bridge failed. In response to those observations, an FIU consulting engineer advised several members of the project team that the engineer of record, W. Denney Pate of FIGG Bridge Group, should be asked to provide a reply. Independent engineers said that the team moving forward with installation indicated that questions regarding the cracks had been resolved.
• Responses from a group of engineers interviewed by the Herald were varied. One engineer said that the cracks should have forced a stop to construction until a full review could be completed, and another reportedly noted that the available photos could have indicated that only epoxy injection remediation was necessary. Yet another engineer told the Herald that the cracks were signs of "imminent failure," leaving the construction and design team with the only option of going back to the drawing board and executing a complete redesign. All of the engineers who were consulted by the Herald said their conclusions could change depending on any new information coming out of the ongoing National Transportation Safety Board investigation.

Dive Insight:

The merits of Accelerated Bridge Construction (ABC), the method used to install the bridge, have also come under scrutiny since the collapse at FIU.

The ABC technique, which sees construction conducted offsite, is widely considered a safer, more efficient way to build a bridge. By constructing components elsewhere and then assembling the bridge onsite, the typical congestion and chaos that occurs in highway and bridge construction work zones can be significantly reduced, increasing both worker and public safety.

There are plenty ABC success stories, including one in Oklahoma. A little more than three months before the FIU collapse, the Oklahoma Department of Transportation used ABC successfully to replace a span of Interstate 235 in Oklahoma City, a phase of work that was part of the agency's  $88 million "Off Broadway" infrastructure initiative. The construction and installation of two spans of the 45-foot-tall, 4-million-pound railroad truss bridge was the ODOT's first ABC project.