Through research on a decommissioned steel-stringer bridge (reinforced-concrete deck on steel girder bridge) in Cincinnati, Ohio, a unique impact test procedure, referred to as "rapid" multi-reference impact testing, was developed and demonstrated as a practical and efficient multi-reference impact test method for bridge condition assessment. It was also demonstrated that a reliable measure of in-situ flexibility, one that properly evaluates/assesses the behavior of the tested region of the bridge, could be computed from the modal data acquired with this particular method. It was believed that "rapid" multi-reference impact methods and the measure of flexibility it provides could be used to assess the structural condition of other steel-stringer bridges. Hence, as a next step, "rapid" multi-reference impact methods were applied to a commissioned steel-stringer bridge that is part of the Ronald Reagan Highway system in Hamilton County, Ohio. This paper summarizes how "rapid" multi-reference impact tests were conducted on this bridge, the challenges of performing these tests while the bridge remained open to traffic, and how the flexibility results detected a change in girder condition from when the bridge opened in the Fall of 1991.
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