Two days before a pedestrian bridge collapsed at Florida International University, killing at least six people, an engineer with the firm that designed the structure called the state and left a voicemail to report cracking in the concrete span.
It went unheard for three days.
“Hey Tom, this is Denney Pate with FIGG bridge engineers. Calling to, uh, share with you some information about the FIU pedestrian bridge and some cracking that’s been observed on the north end of the span, the pylon end of that span we moved this weekend,” Pate said.
“Um, so, uh, we’ve taken a look at it and, uh, obviously some repairs or whatever will have to be done but from a safety perspective we don’t see that there’s any issue there so we’re not concerned about it from that perspective although obviously the cracking is not good and something’s going to have to be, ya know, done to repair that. At any rate, I wanted to chat with you about that because I suspect at some point that’s gonna get to your desk. So, uh, at any rate, call me back when you can. Thank you. Bye.”
It was uncertain if those cracks, observed at the north end of the 950-ton structure, contributed to the catastrophic collapse on Thursday. The National Transportation Safety Board, when questioned about the cracking on Friday night during a briefing on the campus, said they’d not yet verified the information or determined how or where the bridge had failed.
“A crack in the bridge does not necessarily mean it’s unsafe,” lead NTSB investigator Robert Accetta said.
Pate reported the cracking on Tuesday in a voice mail message left with the Florida Department of Transportation Tuesday. Pate, in the call, acknowledged the structure would need repair but downplayed the significance of the problem.
FDOT said the voicemail wasn’t heard by any of its employees until Friday, the day after the bridge fell.
“This voicemail was left on a land line and not heard by an FDOT employee until Friday, March 16 as the employee was out of the office on assignment,” the department said in a late evening press release. “When the employee returned to his office today, Friday, March 16, he was able to listen to the voicemail.”
Through a spokeswoman, FIGG responded late Friday, stressing the ongoing investigation and saying they are “carefully examining the steps” taken by their team during the construction of the bridge.
“The evaluation was based on the best available information at that time and indicated that there were no safety issues,” the company said. “We will pursue answers to find out what factors led to this tragic situation, but it is important that the agencies responsible for investigating this devastating situation are given the appropriate time in order to accurately identify what factors led to the accident during construction.”
Florida International University released its own statement after midnight, explaining that the state was notified of the cracking during a 9 a.m. Thursday meeting.
“The Design Build Team of MCM and FIGG, convened a meeting at the MCM trailer, located on the construction site, to discuss a crack that appeared on the structure. The FIGG engineer of record delivered a technical presentation regarding the crack and concluded that there were no safety concerns and the crack did not compromise the structural integrity of the bridge. This meeting lasted approximately two hours and included FIU and FDOT representatives.”
Some amount of cracking is not unusual in concrete construction. Cracks can be merely cosmetic and no threat to structural integrity or potentially a sign of a more serious problem.
The FDOT information is the latest statement from the agency asserting that FIU and its contractors, Munilla Construction Management and FIGG, had overall responsibility for the project.
FDOT also said Friday that it had issued a blanket permit allowing for two-lane closures effective from January through April, but never received a request to close the entire road and was unaware of any scheduled stress testing of the bridge, which Miami-Dade County Mayor Carlos Gimenez confirmed took place Thursday. The agency said it would have agreed to close the road if there was a risk to motorists.
“Per standard safety procedure, FDOT would issue a permit for partial or full road closure if deemed necessary and requested by the FIU design build team or FIU contracted construction inspector for structural testing,” the state said.
In its Friday press release, the state said that FIU called a meeting of its bridge team Thursday that was attended by an FDOT official, and there was no mention of “life-safety issues.” It’s unclear if FDOT, which did not respond to questions Friday night, was referring to the 9 a.m. meeting, or if the agency was suggesting that the cracking was not discussed.
“The responsibility to identify and address life-safety issues and properly communicate them is the sole responsibility of the FIU design build team. At no point during any of the communications above did FIGG or any member of the FIU design build team ever communicate a life-safety issue.”
Pate, senior vice president and principal bridge engineer at FIGG, is a highly respected engineer who has been with the company for nearly 38 years at its Tallahassee headquarters. He is a central executive in the bridge crew contracted by FIU to design and build the bridge. The blueprint schematics of the bridge bear Pate's “professional engineer” stamp with his license number and a date of Dec. 9, 2016.
He is credited by the industry for creating a “revolutionary cradle system that significantly improves the service life of a bridge and reduces initial construction costs,” according to the American Road and Transportation Builders Association.
Pate, 61, graduated with bachelor’s and master’s degrees in civil engineering from Auburn University and wanted to build bridges since he was eight years old, he told Florida Trend magazine.
The cradle design earned Pate his first patent and a place in the History Channel's "Modern Marvels" selection of important inventions. The idea came to him in 2000 as he wrestled with the design of a Toledo, Ohio, bridge, he told Florida Trend magazine. The system uses individual sleeves to carry strands through a pylon, rather than anchoring individual cables from the road to the pylons, allowing the strands to act independently. Engineers can monitor the individual strands and replace them without closing the bridge.
His projects include the Sunshine Skyway over Tampa Bay, the Chesapeake and Delaware Canal bridge and the Varina-Enon bridge in Virginia.
NTSB investigators are examining a number of factors leading up to the collapse. The federal investigators confirmed an earlier report from U.S. Sen. Marco Rubio that bridge workers were tightening two tension cables inside support trusses located at the northern end of the structure. The work was supposed to strengthen the truss.
They are not expected to issue formal findings for months, if not longer. The state and local police are also investigating.
Miami Herald reporters Douglas Hanks and Andres Viglucci and Monique Madan contributed to this report.