Shear Behavior of RC Beams with Corroded Stirrups Strengthened Using FRP Laminates: Effect of the Shear

Abstract

Externally bonded reinforcement fiber-reinforced polymer (EBR FRP) laminates have been used around the world for the shear strengthening of reinforced concrete (RC) beams with corroded stirrups. The shear span-to-depth ratio (av/d) can significantly influence the behavior of an RC beam shear strengthened with EBR FRP composites and can even determine the shear failure mode of RC beams. Therefore, 18 RC beams were constructed and tested in this study to analyze the effect of the av/d ratio on the performance of RC beams with corroded stirrups strengthened in shear with U-wrapped carbon fiber-reinforced polymer (CFRP) strips. The investigated parameters included three stirrup corrosion levels (0%, 5%, and 15%) and different shear span-to-depth ratios (av/d = 1.0, 2.0, and 3.0). The test results indicated that the high corrosion level of the stirrups significantly decreased the shear capacity of both the strengthened and unstrengthened beams. The experimental results were compared with those of established models provided in the literature. The design formulation was conservative for both the unstrengthened and strengthened beams with different stirrup corrosion levels.