calculating the ductility coefficient (m) of composite columns by using experimental results and the finite element (f.e.m) software

In recent years, structures with cft columns have gained a lot of popularity and they are used in high-rise structures and arched bridges, especially in the far east region such ab s china and japan. in this research, the purpose of which is the effect of concrete strength on the ductility coefficient of cft columns, two models named models a and b were used and for modeling the designed samples, from the abaqus finite element software solid element was used to model concrete and shell element was used to model steel sections. according to the investigations, an unreasonable and illogical result was observed, which indicated the lower design of valid codes such as eurocode (ec4) and aisc. therefore, it is necessary to have the laboratory results presented by reliable laboratory sources and articles in reliable journals and the results of the experiments of this research, providing a correction coefficient about the current and final resistance provided by the relationships.