Repair of I-65 Expressway Bridges Using Carbon Fiber Reinforced Polymer (CFRP) Composites

Abstract

This report documents the repair of five locations along the I-65 Expressway in Jefferson County, Kentucky. The repair involved: (1) the precast prestressed concrete (PC) girder spans between Jacob Street and Gray Street, (2) the reinforced concrete bearing pads of Bridge Pier 4 at the intersection of Jefferson Street and Preston Street, (3) the reinforced concrete bearing pads of Bridge Pier 6 near the intersection of Main Street and Hancock Street, (4) the precast prestressed concrete girder spans between Chestnut Street and Gray Street and (5) the reinforced concrete pier column on East Muhammad Ali Boulevard. The precast prestressed concrete girders were wrapped with carbon fiber reinforced polymer (CFRP) fabrics at the cracked locations to prevent or limit excessive translations in both vertical and horizontal directions. Two of the prestressed concrete girders were instrumented with linear variable displacement transducers (LVDTs) to gauge the effectiveness of the repair before and after retrofit. The wrapping appears to have curtailed the relative movements in the horizontal direction as they are more stabilized and less volatile than before the repair. However, the relative movements of the vertical direction were still apparent. The bearing pads of Bridge Piers 4 and 6, as well as the pier column on E. Muhammad Ali Boulevard, have been repaired and wrapped with CFRP fabric to increase their capacity. The bearing pads of Bridge Pier 6 presented a unique challenge as the pads were irregularly shaped. 'Reshaping' of the pads was performed so that the wrapping would be effective.