Effects of Mid-Strengthening on Stability Analysis of Composite Cylindrical Shell Under External Pressure

Results of a numerical study into buckling behavior of cylindrical laminated shell with, and without mid-strengthening subjected to uniform hydrostatic pressure are discussed. Compared with the conventional ring-stiffened cylinder shell, it can greatly improve pressure resistant capabilities of the shell with only small increase the weight. The finite element method based on ABAQUS used to simulate and analyze the buckling behavior of the pressure shell. The model was about 300mm inner diameter, 700mm long and had uniform thickness of 4mm. The buckling pressures were in the range from 0.75 to 1.82Mpa under different parametric of the reinforced structure. The main work and conclusions are mentioned below: (1) Mid-strengthening structure can improve the critical buckling load of cylindrical shell significantly, buckling mode and maximum amount of deformation will both change; (2) The critical buckling load of cylindrical shell with mid-strengthening gradually increases at first and then decreases with increase in ply angles of reinforced layers; (3) When the width of the reinforced stiffener is inversely proportional to its thickness, the critical buckling load also increases at first and then decreases with the increase in widths of reinforced layers. The results of this study can provide a reference for designing similar composite cylindrical shell under external pressure.