Shear retrofitting of reinforced concrete beams: A critical review

Identifying effective retrofitting solutions for existing reinforced concrete (RC) elements remains a significant challenge, particularly when structures must accommodate increased loading demands due to changes in occupancy or evolving design standards. Many aging RC structures fail to meet current seismic design codes, rendering them vulnerable to brittle shear failure during earthquakes, especially in components lacking adequate shear reinforcement. Traditional retrofitting techniques, such as carbon fiber-reinforced polymers (CFRP) or steel jacketing, while effective, are often intrusive and difficult to implement in confined spaces. Recently, alternative approaches, including hybrid techniques and mechanical anchoring systems, have emerged to address these challenges. This work reviews the advantages, limitations, and applications of both traditional and modern methods, focusing on their mechanical behavior, installation requirements, and seismic retrofitting suitability. The findings aim to contribute to a broader understanding of retrofitting methods and support the selection of context-appropriate solutions for improving structural integrity and safety. This project supports sustainability by preserving resources and cutting emissions through retrofitting instead of demolition. This strategy aligns with Life Cycle Assessment (LCA) principles, as it prolongs the functional lifespan of existing structures and minimizes environmental impacts across all stages of their life cycle.