Contradicting the National Transportation Safety Board’s report that blamed too-thin gusset plates for the Aug. 1, 2007, collapse of the Minneapolis Interstate 35W bridge, an independent analysis has concluded that rusted, frozen roller bearings prevented thermal expansion and caused a truss chord to fail, triggering the gusset-plate failure. The analysis by Thornton Tomasetti, New York City, using forensic bridge information modeling, was presented to victims’ families and will be deployed in an anticipated lawsuit against URS Corp., San Francisco, and Progressive Contractors Inc., Minneapolis, in the next few months, according to Chris Messerly, one of the pro bono lawyers with Robins Kaplan Miller & Ciresi LLP, Minneapolis.
“Our experts’ findings confirm that URS, the engineering company hired by the state to ensure the safety of the bridge, and PCI, the construction company who chose to pile its materials on the bridge rather than keeping them just off the bridge, are responsible for this catastrophe,” says Messerly.