Monitoring system provides decade of data from I-35W bridge

On August 1, 2007, the I-35W Saint Anthony Falls Bridge collapsed in Minneapolis. Its replacement, open to traffic just over a year later, was instrumented with more than 500 sensors to record the new structure’s behavior and evaluate the effectiveness of different monitoring strategies. A 10-year review of the bridge’s monitoring system is now available from U of M researchers.

“The measurements collected over the 10 years of monitoring, with the aid of material tests, truck tests, and finite element modeling, provide insight regarding the relative strengths of the instrumentation systems and potential considerations for future system deployments,” says Lauren Linderman, assistant professor in the Department of Civil, Environmental, and Geo- Engineering (CEGE) and the project’s principal investigator…

One key finding from the project is that seasonal and daily temperature variations have a big impact on the bridge’s behavior. As a result, the instrumentation needed to measure temperature and its impacts is the most important for long-term monitoring.