Influence of Reinforcement Load Level on Bearing Capacity of RC Beams Externally Reinforced with СFRP

Abstract

Most of the experimental investigations devoted to the study of the stress-strain state of bent reinforced concrete elements reinforced with carbon fiber-based polymer-composite materials have examined only unloaded beams or beams without preliminary cracks. However, reinforcement of real load-bearing structures is most often performed under load and taking into account previously occurring defects. At the same time, there are a limited number of systematic studies of the effect of preload on the bearing capacity of reinforced concrete beams reinforced with carbon fiber. This article presents a methodology for assessing the effect of the stress-strain state level of reinforcement on the bearing capacity and other parameters of the sections of bent reinforced concrete elements reinforced with carbon fiber, taking into account the physical nonlinearity of concrete and using real deformation diagrams, including reinforcement and reinforcement systems. On the basis of the developed method, numerical studies of the operation of reinforced concrete sections reinforced at various stages of SSS were performed. After analyzing the obtained data, we can conclude that the level of reinforcement load has a significant effect on the deformability, rigidity and strength of normal sections of reinforced concrete beams and the need to take this factor into account when calculating bending reinforced concrete elements. After analyzing the data obtained, we can conclude that the influence of the reinforcement load level on the deformability, rigidity and strength of normal sections of reinforced concrete beams and the need to take this factor into account when calculating bending reinforced concrete elements.