Gusset plates on the Minnesota bridge that collapsed this summer already showed signs of weakness in 2003 photos just released by the National Transportation Safety Board, reports the Minneapolis Star Tribune. Two bowed plates were located at junctions already suspected by investigators to be the first points of failure in the deadly collapse, and had been previously reported as “under-designed” by authorities.
The accident killed 13 people and injured 145. Minnesota transportation officials closed another bridge last week following concerns about metal plates on that span. The photos were part of a regularly scheduled release of information leading up to the NTSB’s final report at the end of the year. (More I-35W bridge stories.)