Strength calculation of eccentrically compressed concrete elements with a composite polymer reinforcement

Introduction. According to experimental data, at a certain design, the strength of eccentrically compressed elements increases due to the work of a composite polymer reinforcement located in a compressed cross-sectional area. However, dependences for calculating the strength of eccentrically compressed elements, represented in acting regulations for the design of concrete structures with a composite polymer reinforcement, appear to be inapplicable for calculating the reinforcement compression stress and, therefore, require refinement.

Aim. To develop a methodology for calculating the strength of eccentrically compressed concrete elements with a composite polymer reinforcement, considering the work of the latter in a compressed cross-sectional area.

Materials and methods. Considering the work of a reinforcement in the compressed cross-sectional area, the methodology of calculating the strength of eccentrically compressed elements was developed taking into account the positions of current design standards and verified by the data of experimental studies performed by domestic and foreign researchers.

Results. The results of methodology reliability tests were obtained using the experimental data of test samples with a carbon, glass, and basalt-plastic reinforcement of various profile types. During the calculation of eccentrically compressed elements using the proposed dependencies for calculating the height of an element compressed cross-sectional area, the accuracy and reliability were established to be comparable with those calculated according to dependencies adopted in current regulations for the design of concrete structures with a composite polymer reinforcement.

Conclusions. The proposed dependencies for calculating the height of a compressed cross-sectional area provide the sufficient accuracy of strength calculations for eccentrically compressed concrete elements both with and without taking into account the compression work of a composite polymer reinforcement. 

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