from the miami herald article,
The FIU bridge was a truss bridge, its designers, the FIGG Bridge Group, confirmed after the collapse. Many have assumed it was a suspension bridge because renderings of the finished structure show a mast with pipes or cables connecting from its tip to the bridge in a sail-like pattern. Observers, including some engineers, have posited that had the mast been in place, the bridge might not have collapsed.
But in fact the mast would have provided no vertical support. FIGG advertised that as a “cable-stayed” bridge, and plans and other materials on the FIU website say the mast was there mostly to dampen vibration, provide some “stiffness” and create dramatic aesthetics.
After studying the engineering drawings on the website with colleagues, Verrastro confirmed the mast had no role in holding up the bridge.
“They definitely didn’t need it,” he said. “It’s there mostly for looks.”
Because the FIU bridge would see no motorized traffic that could strike a truss, the decision to go with that design by itself raises no red flags, Verrastro said.
