SCI-73-11.93

Korda was retained to prepare a Structure Type Study and Hydraulic Report for the replacement of two structurally deficient bridges on State Route 73. The existing bridges were three span continuous concrete slab bridges on capped pile substructures with sufficiency ratings of 54.1 and 49.7. The bridges span Bear Creek and Saw Pit Run near the intersection of SR 73 with County Route 41.

Korda was able to determine through the study that the bridges could both be replaced using single span structures. The single spans will allow the stream free flow and eliminate the potential for debris collection. To accommodate the single spans Korda designed composite prestressed concrete wide flanged I beams with reinforced concrete decks on semi-integral abutments on piles driven to bedrock. The new bridge over Bear Creek is a superelevated, 91.87 feet long and 36 feet wide bridge to accommodate the curvature of the roadway. The new bridge over Saw Pit Run is on a tangent and is 93.2 feet long and 32 feet wide. Traffic was maintained on SR 73 by the use of one lane, two-way traffic by the use of temporary signals. The bridges were built in phases with final closure pours to compensate for the differential deflections. Wide flange prestressed I beams were incorporated to provide stability in shipping and a quicker timeframe from construction letting to final completion.