الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Behavior of RC beams strengthened in shear with prefabricated UHPFRC plates was investigated experimentally. 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; (i) one longitudinal side strengthening (ii) two longitudinal sides strengthening. Moreover, strengthening RC beams with reinforced or non-reinforced prefabricated UHPFRC plates was also investigated. Moreover, a 3D finite element model of the tested beams was developed using the finite element package ABAQUS to predict the behavior of the tested specimens. The adhesive layer was simulated using cohesive surface model to consider the slippage between concrete surface and UHPFRC plates. The reliability of the proposed numerical model has been validated using the experimental results of the tested beams. Results of the FEM showed good agreement with experimental results; as they were able to predict the behavior of the beams with high accuracy. Additionally, the FEM was used to investigate numerically crucial parameters of the examined technique, which have not been investigated experimentally. Parameters, which are mainly related to the design of this technique, such as effect of shear span to depth ratio, effect of UHPFRC plates‟ thickness, effect of the UHPFRC plates‟ reinforcement ratio, effect of UHPFRC plates‟ compressive strength, and torsion effect on mechanical performance of RC beams strengthened in shear with prefabricated UHPFRC plates have been analyzed numerically. Additionally, the bond mechanism between prefabricated UHPFRC plates and concrete using double bond testing has been investigated. A total of five RC specimens strengthened using different UHPFRC plates‟ lengths and widths were experimentally tested. Also effect of concrete grade was considered through the double shear tests to investigate the bonding behavior of existing RC structures strengthened with UHPFRC systems. Moreover, experimental tests have been simulated by adopting a numerical bond-slip model using finite element method. The proposed numerical model has been verified against the experimental results, showing good correlation. It is expected that the model will provide engineers with a basic design guideline to design safe externally bonded UHPFRC plates‟ reinforcement for RC structures.