Walking through a field of mangled 35W bridge debris in Afton, Minn., anticipation is written all over Don Weinkauf's face. The dean of the School of Engineering has been working with the Minnesota Department of Transportation for more than five years, waiting for this moment. Weinkauf walks me over to a pile of debris that has been pulled aside for St. Thomas, the University of Minnesota and Purdue University, and points to a 5,500 pound slab of green, rusting steel.
A gusset plate.
If there was one engineering term that was thrown around repeatedly in the wake of the bridge collapse, it was “gusset plate.” The National Transportation Safety Board ultimately determined that the failure of one of these plates, too thin by half for a bridge that was placed under increasingly heavy loads during its 40-year life, was what led to the structural undoing of the span. The plate that Weinkauf points to isn’t the plate that failed, but it is one of the three others that failed in rapid succession after the first.
The gusset plate is one of three pieces, totaling 11,000 pounds, that Weinkauf now watches workers load onto a flatbed for transport back to St. Thomas. He may be smiling over the achievement of a goal long sought, but his purpose in bringing these pieces to campus could not be more serious – to remind his students of the incredible responsibility they take on when they engage in their craft. Ultimately he hopes to have each graduating student take an oath, within sight of this steel, that they will remember the burden their work must bear.
The pieces now rest behind Brady Education Center, and they will eventually be reassembled near the Frey Science and Engineering buildings. But for today, walking among the ever shrinking piles of steel in Afton (most of which will be gone by the end of the week – shipped to Wisconsin to be recycled into steel for cars), I can’t help but imagine these pieces as they once stood, even as I photograph them where they now lay as a broken field of green and rust.
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