Stress-strain State of RC Beams Strengthened with CFRP at different Levels of Loading

Abstract

Strengthening of RC structures strengthened by externally bonded CFRP is quite popular all over the world, being in many situations an alternative to traditional methods. However, in most studies, bending elements strengthened by CFRP are considered without loading that have previously arisen in the process of exploitation, which is not entirely correct. At the same time, there are a limited number of systematic studies of the effect of preload on the bearing capacity of RC beams strengthened with CFRP. This article presents a method for assessing the effect of the magnitude of curvature during strengthening on the bearing capacity and other parameters of the sections of bent RC elements strengthened by externally bonded CFRP. On the basis of the proposed technique, numerical studies of the stress-strain state of sections of RC bending elements, strengthened at different levels of initial curvature of an unreinforced section, taking into account different coefficients of reinforcement with steel reinforcement, were performed. After analyzing the obtained data, we can conclude that the level of curvature of the section during strengthening has a significant effect on the deformability and strength of RC beams and the need to take this factor into account when calculating bending RC.

Keywords

• rc beams
• reinforcement load
• externally bonded
• сfrp
• stress-strain state