Reinforcement of RC beams with special fibrous blocks/panels against shearing

With developments in concrete technology, the use of ultra high-performance fibre concretes in construction is becoming more widespread. Ultra High-Performance Fibre Concrete (UHPFC) has many applications in civil engineering due to its fibre structure and its advantages such as high strength, high durability and high ductility. The use of UYPLB is becoming increasingly widespread, particularly in the strengthening of structures. In reinforced concrete structures, damage occurs to the structural elements due to effects such as earthquakes and fire, as well as the poor quality of the materials used in the building stock, the lack of inspection and engineering services. Depending on the type of damage that has occurred, the structural elements are reinforced and the appropriate method of reinforcement is chosen, taking into account the type of damage, the use of the structure and the cost of reinforcement. One of the damages that occur in structural elements is the shear damage in reinforced concrete beams due to insufficient and inappropriate reinforcement detailing. The aim of this thesis is to strengthen reinforced concrete beams with insufficient shear strength, as a different and new strengthening method, with special fibre blocks/panels with advanced mechanical properties. To this end, 6 samples of beams with inadequate shear strength have been experimentally tested. In order to investigate the effect of special fibre blocks/panels on the beam element, 1 out of 6 reinforced concrete T-beams in ½ scale samples was selected as a reference sample. The 5 beams produced were of the prefabricated type reinforced by bonding special fibre blocks/panels with different geometric dimensions and application principles to the relevant parts of the beam with high strength epoxy. The special fibre blocks/panels were fixed in different ways with certain spacings and the block model surrounding the beam, similar to the stirrup spacing, and the optimum type of reinforcement was determined by testing its performance. According to the results obtained, 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 %. The most optimal model was observed for the type of reinforcement where the beam was formed as a fully confined beam. With this type of reinforcement, very good results were obtained in the beam, especially in terms of ductility and energy consumption performance. In addition, one of the important advantages is that the reinforcement method proposed in the study, using special fibre blocks/panels, is more economical than other reinforcement applications, is made from readily available materials, does not require special labour and is easy to apply due to its prefabrication production practicality.