The numerical analysis of the long-term behaviour of the reinforced concrete beams strengthened with carbon fibre reinforced polymer: Cracking

Abstract

The paper presents the analysis of the long-term deformability of the reinforced concrete beams strengthened with CFRP. The analysis is based on the obtained numerical and experimental data. The development of deformations is divided into stages. The comparison of the cracking process in the compressed and tensioned areas is performed. The comparative analysis of the results has shown that more attention should be paid to the creep of concrete and the influence of the tensioned reinforcement when the external load is decreased. The study has shown that the compression of the section subjected to long-term loading turns into tension when the external load is removed. Due to the effect of the tensile force, cracks appear on the top of the compressed section. Therefore, re-loading of the beam requires further evaluation of the strength degradation in the concrete of the compressed area.