نوع مقاله : مقاله پژوهشی
1 دانشیار، دانشکده مهندسی عمران، دانشگاه سمنان، سمنان، ایران
2 دانشکده مهندسی عمران، دانشگاه سمنان، سمنان، ایران
عنوان مقاله [English]
In this paper, a strengthening method based on embedded carbon fiber reinforced polymer (CFRP) strips in near surface on concrete cover was applied for improving flexural capacity of reinforced concrete columns with low strength compressive concrete subjected lateral cyclic loads. The debonding phenomena is prevented in this suggested method and the strip capacity is completely used and there is more protection against fire. In order to investigate the flexural behavior of near surface mounted (NSM) strengthened RC columns, a finite element method is sued. poly-linear behavior of concrete and steel was used. There was good similarity between finite element and experimental results that indicates suggested model was calibrated. The new models consisting of different variables such as embedded steel bar diameter, concrete strength, and the numbers of CFRP strips were considered. The test results show that by using the NSM technique, the flexural strength and lateral load capacity of the columns increase significantly. The numerical results were also compared with the results obtained from the analytical study that was conducted based on strain compatibility. A good agreement between analytical and experimental results was observed.
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