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This paper presents the efficiency of using prefabricated ultra‐high performance fiber reinforced concrete (UHPFRC) plates in shear strengthening of reinforced concrete (RC) beams experimentally and numerically using finite element method. In order to ensure high quality and facilitate the strengthening process on site applications, it has been considered to apply UHPFRC as a plate pasted on concrete surface using epoxy. Tested specimens included four strengthened beams besides three control beams. Strengthening the RC beams was based on the use of two different techniques; (a) one longitudinal side strengthening (b) two longitudinal sides strengthening. Moreover, strengthening RC beams with reinforced or non‐reinforced prefabricated UHPFRC plates was also investigated. Results show that UHPFRC plates significantly increased the maximum load capacity, ductility and mid span reinforcement strain of the strengthened RC beams comparing with reference beam failed in shear. Also, steel connectors used in reinforcement of UHPFRC plates prevented debonding failure mode. A three‐dimensional (3D) finite element model (FEM) of the tested beams was also developed to predict the behavior of these specimens strengthened in shear. The adhesive layer was simulated using cohesive surface model to consider the slippage between concrete surface and UHPFRC plates. Results of the FEM showed good agreement with experimental results, as they were able to predict the behavior of the beams with high accuracy.

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This paper investigates the behavior of RC beams strengthened in shear with UHPFRC. In order to ensure high quality and facilitate the strengthening process on site applications, it has been considered to apply UHPFRC as a plate pasted on concrete using epoxy. In addition to the control beam, two strengthened RC beams using prefabricated UHPFRC plates were prepared and tested. All beams had the same rectangular cross-section geometry (150mm x 300mm x 2000mm). Two different techniques were considered during the strengthening process; the first application was the addition of two 30 mm UHPFRC plates, whereas the second beam strengthened using one 60 mm UHPFRC plate. Results showed that strengthening RC beams using two UHPFRC plates improved load carrying capacity with 145 % comparing with the control beam. Moreover UHPFRC plate in case of strengthening one side of the RC beam prevented shear cracks from appearing on the strengthened side.