Flexural strengthening of prestressed bridge slabs with FRP systems

Fiber reinforced polymer (FRP) materials offer great potential for cost-effective retrofitting of concrete structures. In response to the growing need for strengthening and rehabilitation of concrete structures and bridges, an experimental program was conducted to investigate the feasibility of using different strengthening techniques as well as different types of FRP for strengthening prestressed concrete members. Half-scale models of a prestressed concrete bridge were constructed and tested to failure. The test specimens consisted of one simple span and two overhanging cantilevers. Each specimen was tested three times using a different load location in each case. Five different strengthening techniques were investigated including near surface mounted Leadline bars, C-Bars, CFRP strips and externally bonded CFRP sheets and strips. Ultimate capacity; failure mechanism and cost analysis of various strengthening techniques for concrete bridges are presented. The applicability of a nonlinear finite element analysis of post-tensioned bridge slabs strengthened with near surface mounted FRP reinforcement is enumerated.