Repair and Upgrade of Prestressed Concrete Beams Using Glass Fiber-Reinforced Polymeric Composite Materials

摘要

As a part of an ongoing Construction Productivity Advancement Research program for the U.S.Army Corps of Engineers, the U.S.Army Construction Engineering Research Laboratory, in partnership with the Composites Institute, evaluated the effectiveness of fiber reinforced composites for upgrading concrete single T-beams which were under-reinforced composites for upgrading concrete single T-beams which were under-reinforced for shear. Results from a study on strengthening of two reinforced concrete beams having deficient shear strength will be presented in this paper. One beam was damaged to a predetermined level and then repaired with a fiber reinforced polymer (FRP) composite U-jacket externally adhered to the web in the beam shear span. One undamaged beam was similarly upgraded. Experimental data on the strength, stiffness, deflection and mode of failure of the repaired/upgraded beams were obtained and comparisons made with unrepaired control beams. The FRP repair was shown to increase shear capacity of the beams, however, proper application of the FRP is critical to obtaining the desired flexural failure mode.