[4] The engineering design error that directly led to the collapse was identified by the National Transportation Safety Board (NTSB) as a miscalculation of resistance to sliding of the connection between the walkway surface, and the truss that held it up.

It is home to the federally funded Accelerated Bridge Construction University Transportation Center, which sponsors industry conferences and seminars.

"[13] The full 320-foot-long (98 m) pedestrian bridge was to cross both a major roadway and a parallel water canal with two separate spans connected at a faux cable-stayed tower.

Kevin Hanson, the supervisor of the de-stressing operation of the PT tendons, became aware that cracks formed on the north side of the bridge and was concerned.

Two days before the collapse, on March 13, the engineer of record (EOR) from FIGG became aware of the cracks and began calculating remedial action, including the addition of plastic shims under the diaphragm.

[2] At 9 a.m. on March 15, a university employee heard a loud "whip cracking" sound while under the bridge span, waiting for a red traffic light.

[2] The FIGG lead engineer's conclusions were that the structural integrity of the bridge was not compromised and that there were no safety concerns raised by the presence of the crack.

[35] An additional measure proposed by FIGG at the meeting to remediate the cracking was telling the contractor that it "must expedite the pouring of the intermediate pylon," a structure that was designed to mimic the tower of a cable-stay bridge.

FIGG promised to deliver the temporary mechanism to capture the forces and node 11/12 by March 17, 2018 to MCM in two days, showing a sense of urgency.

The street closure was warranted due to the inadequacy of the node to support the loads during Stage 3, until all the remedial measures were designed, evaluated, peer reviewed and implemented or until the intermediate pylon was constructed.

FIGG knew that the engineer who performed the peer review did not check the bridge design during different stages of construction, in violation of the FDOT requirements.

They deferred to FIGG's conclusions, and failed to apply their own judgement and judiciousness, even though FDOT, BPA and MCM have extensive experience in bridge and concrete construction.

Immediately after the meeting between FIGG employees and FIU, FDOT, BPA (Bolton Perez and Associates, Inc., the construction engineering and inspection firm), and MCM (the main construction contractor); the pretensioning crew from Structural Technologies (US licensee of VSL tensioned-concrete technology) began to re-stress the two PT rods in diagonal truss member 11 to 280,000 pounds each.

Due to the urgency and short notice demanded by the EOR, the post-tensioning inspection subcontractor, the Corradino Group, was unavailable to monitor this process.

[2][36] United States Senator and FIU adjunct professor Marco Rubio tweeted that engineers were tightening loosened cables on March 15:[37] "Workers were adding more tension to the steel rod (tendon) inside a concrete diagonal strut at the north end".

The other people killed were Alberto Arias, 53, Brandon Brownfield, 39, FIU student Alexa Duran, 18, Rolando Fraga, 60, and Oswaldo Gonzalez, 57.

Additional, in the interest of full transparency, FDOT is today releasing the transcript of a voicemail left on a landline on Tuesday, March 13, by W. Denney Pate, FIGG's lead engineer responsible for the FIU pedestrian bridge project.

On Wednesday, March 14, Alfredo Reyna, the Assistant LAP Coordinator and an FDOT consultant, received a phone call from Rafeal Urdaneta, a Bolton Perez & Associates employee, notifying him of a midday meeting scheduled for Thursday, March 15 with W. Denney Pate and other members of the FIU design build team that are responsible for the project.

Reyna attended the meeting which occurred shortly before the bridge failure and collapse and was not notified of any life-safety issues, need for additional road closures or requests for any other assistance from FDOT.

[50][51]On March 21, 2018, the NTSB sent out a press release detailing the items from the collapse that required further examination at the Turner Fairbank Highway Research Center, in McLean, Virginia.

[52] On May 23, 2018, the NTSB released a preliminary report titled "Highway: Collapse of Pedestrian Bridge Under Construction Miami, Florida (HWY18MH009)" which summarized the accident.

[44][53] The Turner-Fairbank Highway Research Center, at the request of the NTSB, tested samples of steel and concrete from the collapsed bridge, and found that the materials met the project requirements.

[57] On March 21, 2018, U.S. Transportation Secretary Elaine Chao asked the department's inspector general to probe whether the federally funded pedestrian bridge complied with all rules.

[58] A subsequent internal memorandum from the Inspector General of the U.S. Department of Transportation, dated March 22, 2018, expressed concerns the project complied with Federal specifications, and that the objective of an audit would be to assess whether the Florida International University pedestrian bridge met Federal and DOT requirements for the TIGER application, approval, and grant agreement processes.

A lawyer for Reporters Committee for Freedom of the Press indicated more information should be released under the Florida Sunshine Law, citing intense public interest in the collapse.

[61] On May 3, 2018, a lawyer for the NTSB wrote a letter to Judge Cooper of the 2nd Judicial Circuit of Florida in Tallahassee urging the court to deny a ruling that would favor the Miami Herald plaintiff, for the release of any bridge information generated after a February 19, 2018, cutoff date.

[62][63][64][65][66] On May 7, 2018, the Miami Herald reported they had received a copy of a memo with photographs from FIU dated February 28, 2018, that had been sent to the Munilla Construction Management company, the bridge project's builder.

The memo, which has since been withdrawn from public view, purportedly urged the bridge engineer to respond to their concerns about significant cracks in the concrete joint at connection between the No.

"[71] The following is from a September 18, 2018 OSHA News Release – Region 4: The U.S. Department of Labor's Occupational Safety and Health Administration (OSHA) on Friday, September 14, cited multiple contractors for safety violations after one employee suffered fatal injuries and five other employees sustained serious injuries when a pedestrian bridge at the Florida International University campus in Miami collapsed.

[77] FDOT announced on May 5, 2022, the new design, a cable-stayed steel box girder bridge built using a conventional six-step construction process with full closure and detour of the roadway beneath.