Approximate calculation method of buckling load on integral sub-stiffened panel

To calculate the integral sub-stiffened panel buckling load in the preliminary design stage quickly, a simplifying approximate calculation method based on some reasonable assumptions was proposed. The perfect rectangular sub-stiffened panel simply supported on four sizes was used as investigation object. This structure has 3 instability forms, and the corresponding buckling loads were obtained by using the traditional stiffened plate theory. The minimum buckling load of the 3 instability forms was regarded as the approximate buckling load of the integral sub-stiffened panel. The buckling linear perturbation step method of ABAQUS was used to calculate the two sets of finite element (FE) models respectively: one set was used to validate the accuracies of the theoretical formulas for failure modes, and the other set was integral sub-stiffened panel finite element models which were used to verify the applicability of proposed calculation method of sub-stiffened panel buckling load. Only two load cases were considered in the research above: the longitudinal compression load and the combination of compression and shear load. The results indicate that the theoretical approximate calculation method can calculate the buckling load of sub-stiffened panel, which count for engineering application to some extent.