A Florida newspaper has concluded that a new video proves workers were atop the Florida International University (FIU) bridge in Miami, tightening steel rods in the concrete just before it collapsed onto a busy road on 15 March, killing six people.
The 174-foot, 950-ton section had been hoisted into place just five days before.
Newspaper The Miami Herald is suing the Florida Department of Transportation (FDOT) over its refusal to release documents and emails that the newspaper says could shed light on the fatal collapse of the pedestrian bridge.
The National Transportation Safety Board (NTSB), a federal agency based in Washington, D.C., is currently investigating the cause of the collapse.
Now, the paper has seized on time-lapse videos, newly released by the university, of the bridge being installed and collapsing on the busy road.
The NTSB has already stated that workers were adjusting two tensioning rods on the north end of the bridge when it collapsed, but the Herald says the videos give "the public’s closest view yet of the deadly accident and the days leading up to it", and says the workers’ actions may have caused the collapse.
The Herald maintains that at least four workers can be seen standing on the bridge moments before it fell. It claims the workers were "using a jack to re-tension, or tighten, the steel rods that ran through a crucial concrete support truss at the bridge’s north end".
"Their actions may have caused the bridge – which was already developing alarming cracks – to come crashing down," the paper writes, adding: "Who ordered the construction crew up there – and why – remains unclear. That information may be contained in documents that the Miami Herald is suing to acquire."
The six time-lapse videos are constructed from a series of still photos taken by FIU cameras from various angles between March 1 and March 19.
"Previously," the Herald writes, "the public has seen only grainy surveillance camera and brief dashcam footage."
Because the bridge was prefabricated and hoisted quickly into place, it was considered a feat of modern construction.
Controversy surrounding its collapse has been fuelled by the fact that the project team building it met that morning to discuss cracking that had appeared, with team members concluding that there were no safety concerns.
Image: Aerial view of the accident site soon after the bridge collapsed (Miami-Dade Police aviation unit via Twitter)