Elastic Buckling of Pressure Loaded Sandwich Cylindrical Shells

The previously postulated reduced stiffness lower bound for laterally loaded sandwich cylindrical shell is compared with the lower bound obtained from the FEM analysis to ascertain its validity. The critical mode shape from the classical bucking analysis was introduced as the initial imperfection shape in the numerical examples. And the analysis was repeated by varying the amplitude of the initial imperfection until a lower bound is obtained from the FEM analysis. Comparison of so obtained FEM lower bound with one obtained with reduced stiffness analysis shows that the proposed reduced stiffness method provides close lower bound for bucking of laterally loaded sandwich cylindrical shells.