Enhancing the shear strengthening of reinforced concrete T-shaped beams using innovative fiber blocks/panels

Abstract

In this study is the strengthening of shear deficient RC beams using special fiber blocks/panels (FB) with advanced mechanical properties and was investigated experimentally. It is aimed to increase the shear capacity and ductility of the RC beams with this innovative and novel method, which can be made in various application configurations. For this purpose, six T- shaped beams in ½ scale were produced and experimentally tested with monotonic loading under four points. All beams were designed to have insufficient shear capacity and were produced accordingly. One of the beams was a reference and the others produced beams were of the prefabricated type reinforced by FB with different geometric dimensions and application principles at the relevant parts of the beam. The FB were fixed in different ways with certain spacings, and the block model wrapped around the beam, similar to the stirrup spacing, and the optimum type of reinforcement was determined by testing its performance. The most optimal model (B5) was observed for the type of reinforcement in terms of ductility and energy consumption performance where the beam was formed as a fully wrap. As a result of the experiments, the strength of the reinforced specimens increased by 36 – 53% compared to the reference beam specimen, and the ductility and energy consumption capacities increased by 61 – 111%. In addition, in this the study proposes a computational equation with an analytically based approach specific to the most effective configuration of the FB. The study compared the capacity gain of FB-reinforced beams with CFRP and GFRP reinforcements of similar configurations in the same beams to evaluate their performance and applicability as an alternative technique and interpreted the results. © 2024 Institution of Structural Engineers