Shear Strengthening of Two-Way Reinforced Concrete Slabs with Openings: A Review of Strengthening Techniques and Code Perspectives

03.Nov.2025

​​Two-way reinforced concrete (RC) flat slabs are widely used in modern buildings because of their architectural flexibility and efficient load transfer. However, the introduction of openings for mechanical and electrical services disturbs the stress flow and considerably increases the risk of brittle punching shear failure. To address this issue, this review systematically investigates the influence of the size, shape, and position of openings on the punching shear behavior of RC slabs and evaluates the effectiveness of major strengthening techniques such as fiber-reinforced polymers (FRP), shear studs, and textile-reinforced mortar (TRM). In addition, it critically examines the accuracy and reliability of international design codes in predicting punching shear capacity. A systematic PRISMA approach was applied to review studies from the Scopus database published over the past 15 years, including experimental, numerical …​