Shear span-to-depth ratio effect on steel reinforced grout strengthened reinforced concrete beams

Abstract

The effect of the shear span-to-depth (a/d) ratio on the shear behavior of steel reinforced grout (SRG)-strengthened reinforced concrete (RC) beams is experimentally investigated. Four critical shear spans corresponding to a/d ratios of 1.60, 2.10, 2.60, and 3.10, representing a range for deep to slender beams were considered. In addition, the effect of the steel fabric density of SRG composites was also explored. Twelve beams were cast in four series of three specimens each. The experimental results demonstrated the strengthening efficacy of SRG for deficient beams in shear. The SRG strengthening enhanced the overall capacity of the beams by more than 130% with an average of 78%. Moreover, the results confirmed the effect of the a/d ratio on the performance of SRG-strengthened beams. The efficacy of the SRG significantly increased with an increase in a/d ratio in deep beams but deteriorated as a/d ratio increase in slender beams. Finally, an analytical model for predicting the shear capacity of SRG-strengthened beams is proposed that captures the effect of the a/d ratio. The model provides accurate and safe predictions with an average of the ratio of the predicted to experimental shear capacities (Vth/Vex) of 0.99 with a standard deviation of 0.068.