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By analyzing building plans and construction photos from the site, AvE concluded that the bridge would have been fine as initially designed, but that it was brought down by shortcuts taken on the construction site.

The main span of the bridge was prefabricated and then swung into position in a single day. This unique design was intended to reduce traffic delays on the six-lane road it would be spanning.

Once in place, the plan was to install the bridge’s final supports while traffic was once again allowed to flow underneath the still-unfinished span.

Photo by Pedro Portal/ The Miami Herald via AP

But photos and video from the swing-out reveals that the heavy-lift vehicles used to move the span were positioned differently than indicated in the bridge’s original plans, which would have placed stress on weaker areas of the bridge. This, in turn, could have upset the latticework of cables holding the bridge together.

Much like the spokes on a bicycle wheel, the concrete bridge (like thousands of other concrete bridges) was held together using a latticework of tension rods strung throughout the structure.

And, just like when a bicycle wheel becomes warped, an improper move of the bridge would have jostled these rods to where they were no longer sharing the load equally.

Photo by DroneBase via AP

This would explain why builders reported cracks in the structure in the days leading up to the collapse. However, engineers continued to deem the bridge safe, according to subsequent statements from FIU.