BUCKLING ANALYSIS OF CORRUGATED CYLINDRICAL STRUCTURES TO ACHIEVE THE HIGHEST STRENGTH-TO-WEIGHT RATIO

Increasing the buckling strength-to-weight ratio is of particular importance in aerospace, mechanical, nuclear, and civil engineering. Corrugated structures with trapezoidal geometric pattern have higher amount of the buckling strength-to-weight ratio with respect to other similar structures; hence, these generations of structures are widely used in several industries. Static stability of corrugated cylindrical structures with trapezoidal geometric pattern was investigated here under axial loading for simply supported boundary condition. Using rst-order shear deformation theory of Mindlin, equilibrium equations of the problem were derived. Mechanical proper ties of corrugated cylindrical structure were achieved by the mechanical properties of equivalent orthotropic circular cylinder. Then, critical buckling load was obtained for both simple circular and corrugated cylinders. The present analytical results are validated by the nite element models. These validations report very good agreement between the present results and those obtained by the nite element analysis. Eect of dierent parameters including number of corrugations, cylinder thickness, cylinder length, cylinder radius, corrugation angle, and shape factor was investigated numerically on buckling behavior of corrugated cylindrical structure. The results of nite element reveal that buckling mode shapes can be divided into two types as local and global buckling modes. Graphical shapes of local and global modes are presented to make the better physical sense. In this article, the present analytical method can solve the global buckling problem of a corrugated cylinder. According to the comparison between present modeling results and those obtained by nite element analysis, increasing the corrugation angle and cylinder radius and decreasing the number of corrugations, the cylinder thickness, the cylinder length, and shape factor led to an increase in the buckling load of corrugated cylinder with respect to circular cylinder on the condition that local buckling had not been occurred. The present results and procedure can help engineers and designers to achieve a best performance for their structures, especially related to aerospace structures.