The Francis Case Memorial Bridge, an arterial structure spanning the Washington Channel of the Potomac River in the center of the nation's capital, carries 8 lanes of I-395 traffic. An extensive rehabilitation program undertaken in 1994 resulted in replacement of the approach spans of the original bridge with precast and prestressed concrete girders made continuous at the piers. During routine inspection of the bridge in 1998, large, full-depth vertical cracks were discovered on the soffit of the beams, near the first interior pier. These were of unusual severity and also of unknown origin. The District of Columbia Department of Transportation, with assistance from the Federal Highway Administration, immediately began stabilizing the cracked girders and initiated an investigation to ascertain the cause, prognosis, and whether the structure could be repaired. This article details the findings of the investigation of the Case Bridge failure.
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