عنوان مقاله [English]
In this paper the effect of primary imperfection, on the buckling pressure of a cylindrical shell under external pressure, has been studied. To obtain the buckling pressure, both linear and nonlinear analysis, using finite element software ABAQUS, and GL and EN standards have been applied. For evaluation of FEM results, a typical problem has been solved and results have been compared with experimental and numerical works and a good accordance have been achieved. In the next section, buckling of a cylinder under external pressure with regard to the primary imperfection analysis, using nonlinear module of ABAQUS software was calculated. According to the weakness of the existing relations in the two standards, a special case of the finite element model results were compared with the standard.