Structural Investigation of the Sherman Minton Bridge Closure

The Sherman Minton Bridge, constructed in the early 1960's, is a twin, double-deck, steel-tied arch bridge traversing the Ohio River along Interstate I-64 between the states of Indiana and Kentucky. The discovery of previously hidden surface cracks during a gusset retrofit warranted a comprehensive inspection program which revealed numerous cracks and weld indications along the fracture critical tie members, particularly at the vertical butt-welded joints. Following the closure of the bridge on September 9, 2011, a structural investigation was initiated to ensure that the bridge would reopen with three principles in mind: safety, schedule and cost. A forensic information model (FIM) of the weld testing inspection program was created to organize available data, illustrate all past and present inspections and to understand any trends. A 3D mathematical model was produced to verify the original design of the superstructure and to evaluate the adequacy of its capacity to support increased loads as a result of the necessary retrofits and repair. This paper will present the process used to evaluate the problem, develop solutions, and construct the retrofit.