Results of computational studies of reinforced concrete structures using an external reinforcement system based on composite materials

Introduction. In the course of the study, a calculated justification of the strength of a reinforced concrete beam reinforced with composite materials was performed. At the first stage, an elastic finite element model was developed to analyze the stress distribution and calculate the required reinforcement area. At the second stage, a nonlinear deformation model of concrete is included, the cracking process is taken into account. Iterative calculations have shown the achievement of the limiting state of the structure. At the third stage, a model with external composite reinforcement was created. The reinforcement reduced the deflection from 7.36 to 6.47 mm, reduced the stresses in the reinforcement by 17.46 % and increased the bearing capacity by 32 %. Experimental studies are planned, including consideration of dynamic effects and temperature and humidity factors.

Aim. The main aim of this study is to investigate the effectiveness of fiber-reinforced polymer-based composite materials for reinforced concrete structures strengthening. The stress-strain states of reinforced and unreinforced structures were also compared.

Materials and methods. Computational studies of reinforced concrete structures were performed using the finite element method with nonlinear models in the ANSYS software package.

Results. The analysis of the stress-strain state of the reinforced concrete structure with and without external composite reinforcement was carried out, allowing for an assessment of the effectiveness of composite reinforcement for improving the strength and durability of the structure. The study models and analyzes the stress-strain state of such structures when using external reinforcement and evaluates the impact of composite materials on stress and deflection reducing, and load-bearing capacity of the structure increasing.

Conclusions. The study results indicate that using of composite materials for external reinforcement of reinforced concrete structures effectively reduces reinforcement stresses, decreases deflection, and prevents crack formation under composite covering. Maximum tensile stresses in the reinforcement were reduced by 17.46 %, and the load-bearing capacity of the structure increased by 32 % (from 126.75 to 167.31 kN).

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