Federal investigator says 'cracking' wasn't necessarily cause of bridge collapse

National Transportation Safety Board: Point of failure appears to be north end


SWEETWATER, Fla. – After a bridge engineer warned state authorities about cracking on the pedestrian bridge that collapsed outside of Florida International University Thursday killing at least six people, federal authorities say report could be irrelevant. 

National Transportation Safety Board investigator in charge Robert Accetta said Friday night workers were tightening a few suspension cables when the tragedy happened. And although that and the engineer's alleged warning could serve as clues, he also said it's too early in the investigation to determine what went wrong. 

"A crack in the bridge does not mean it’s unsafe," Accetta said. 


NTSB chairman Robert Sumwalt said Accetta and his team were committed to finding out what went wrong in what he thought was going to be a complicated and extensive investigation. They plan on spending about a week on the site in Miami-Dade's Sweetwater before heading back to Washington to compile their findings and report their recommendations. 


The Occupational Safety and Health Administration and the Federal Highway Administration are also conducting investigations on what went wrong about 1:30 p.m. on Eighth Street at Southwest 109th Avenue. FIU students were on spring break. 

"We want to look at how the contractors identified risk and mitigated risk," Sumwalt said about the focus of their probe. 


Denney Pate, the engineer who warned the Florida Department of Transportation about "some cracking on the north end of the span" two days before the collapse worked for Tallahassee-based FIGG Engineering Group, the contractor involved in the design of the bridge.    


"From a safety perspective, we don't see that there's any issue there, so we are not concerned about it from that perspective --- although obviously the cracking is not good," Pate said in a voicemail he left after calling an FDOT official, who was out on assignment and said he didn't get the message until Friday. 


Accetta said the bridge, designed to connect FIU's Modesto A. Maidique campus with the sidewalk in Sweetwater, was missing its center beam, but that was not an integral part of the structure. He said it was more of a "cosmetic" element and was not a part of the innovative method used. He was more concerned about the workers applying post-tensioning force before the collapse. 


"There were two cables that they were working on at the time," Accetta said. "I don’t know if that was a point of failure. The cables were at the north end of the bridge."


Sumwalt referred to a video of images from a traffic camera that was leaked on social media, and showed the moment when the bridge's 174-ton concrete platform squashed several cars and created a cloud of dust. Investigators signaled the video will support their focus on the north end of the bridge.


"Based on video that’s on the Internet, it appears that was the point of failure, but there is still work to be done to determine that," Sumwalt said. 


FIGG Bridge Engineers released a statement saying they were working with the construction team to determine the cause of the collapse. The company spokesperson added in a statement that the engineer's "evaluation was based on the best available information at that time and indicated that there were no safety issues."


FIU president Mark Rosenberg said the $14.2 million project received federal funding and although FIU was managing it, the bridge was a coordinated effort between federal, state and local authorities. He added the project had the safety of students in mind and had been a source of celebration Saturday when the main span was installed. 


Rosenberg said the project began in 2010. Sen. Marco Rubio tweeted the project was part of an $11.4 million federal grant awarded to FIU in 2013.



Miami-Dade Police Department homicide investigators were working closely with the Miami-Dade State Attorney's Office to protect and collect evidence.  


"Our primary focus is to remove all of the cars and all of the victims in a dignified manner and not compromise the investigation in the process," Miami-Dade County Deputy Mayor Maurice Kemp said.


Authorities had yet to identify the victims, but the relatives and friends of 18-year-old Alexa Duran, a student at FIU, said she died in her car while driving a friend to a doctor's appointment. VSL Structural Technologies announced Navaro Brown, 37, died when a company pickup truck was crushed. 



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