Retrofitting reinforced concrete beams against shear failure using Carbon Fiber-Reinforced Plastics: Addressing the limitations of monolithic beam-slab systems

The use of Carbon Fiber-Reinforced Plastics (CFRP) for retrofitting reinforced concrete (RC) beams against shear failure has gained significant attention due to its high strength-to-weight ratio and ease of application. However, current design codes and experimental studies often overlook the practical constraint imposed by monolithic beam-slab construction, where FRP wrapping can only be applied to a portion of the beam depth. This paper reviews the state-of-the-art in CFRP retrofitting, highlights the limitations of existing approaches in addressing monolithic systems, and presents findings from a finite element analysis (FEA) that investigates the shear behavior of partially wrapped beams. The results suggest that partial-depth CFRP application alters stress distributions and shear capacity, necessitating revisions to design guidelines. Recommendations for integrating these findings into practice are proposed.