Shear strengthening of a PC bridge girder with NSM CFRP rectangular bars

Bridges worldwide are falling into a state of disrepair caused by deterioration, traffic overloading, and poor maintenance. It is estimated that over 100,000 of the half million existing bridges in the US are in need of repair or replacement. Although the full replacement option could be viable, it is an expensive solution with significant disruption of service. This paper focuses on the use of carbon fiber reinforced polymer (CFRP) rectangular bars installed as near surface mounted (NSM) reinforcement for shear strengthening in conjunction with an externally bonded pre-cured CFRP laminate to increase the flexural capacity of a prestressed concrete (PC) bridge girder. The specimen, which was removed from an overloaded bridge in Kansas was strengthened and tested in the laboratory. Test results showed that the proposed NSM reinforcement technique represents an effective solution to increase shear capacity.