Thornton Tomasetti was engaged to investigate the cause of the August 1st collapse of the 1,900-foot-long Interstate Highway 35 West bridge over the Mississippi River in Minneapolis, in which about 145 people were injured and 13 died.
Thornton Tomasetti’s investigation into the cause of the collapse included on-site observations, review of more than 50,000 documents, and detailed analysis of the entire bridge. The analysis, conducted on behalf of a consortium of 20 Minnesota law firms representing more than 90 victims and their families on a pro bono basis, were completed by the one-year anniversary of the event, when the National Transportation Safety Board had to report its findings.
Studies by the advanced analytics team included assessing the impact of fatigue, temperature and load redistributions on critical bridge members subjected to static and dynamic loads. A key component of the work was the construction of a forensic information model, an interactive, computer graphic model of the bridge that enabled engineers to catalog and access available information on each bridge component. Simply clicking on a girder or connection brings up all the known information about that member.
Location: Minneapolis, Minnesota
Client: Robins, Kaplan, Miller & Ciresi L.L.P.
Completion Date: 2008