بررسی اثر تقویت کننده‌ها بر بار کمانش پوسته استوانه‌ای کامپوزیتی

 The aim of this article is the survey of the effect of several parameters of stiffeners on the buckling load of the composite cylindrical shell. The used composite material is laminate and shell equations are derived using energy approach and the principle of minimum potential energy. Also shell equations are based on the first-order shear deformation theory of shells and boundary conditions are assumed to be simply support. The ring and stringer stiffeners are treated as discrete elements from shell and the effects of different terms are related to each other using continuity equations. The effects of several parameters are surveyed such as number of ring and stringer stiffeners, geometrical parameters of stiffeners and distribution pattern of them and related graphs are drawn. Also in order to surveying the effects of all parameters on buckling load simultaneously, each parameter is assumed as a design variable and optimization is performed based on the assumption of equal weight for un-stiffened and stiffened shell by genetic algorithm approach. Finally, the obtained results are presented.