behavior comparison of uniaxial cylindrical columns strengthened with cfrp

In recent years application of cfrp sheets in the strengthening of the concrete circular column has increased numerously. knowing the exact behavior of concrete cylindrical columns confined with cfrp is of the first order of importance. isis code of canada has given relations for strength increase of circular columns confined with cfrp sheets, these relations are defined for a specified range of confinement pressure, and for higher confinement pressures there are no relations describing the behavior of the confined specimen. in this paper, cylindrical specimens with different concrete strengths and a variable number of cfrp layers were used. they were modeled in finite element software. after verification of models with laboratory works; results of finite element modeling were compared with isis canada. the analytical results show that with a change in concrete strength the results have a different error from isis results. therefore, for confinement pressure of more than the permissible value of isis code, change in the amount of strength increases was studied.