Influence of Random Geometric Imperfection Morphology on Localized Buckling of Axially Compressed Cylindrical Shells

Initial geometric imperfections strongly affect the buckling resistance of cylindrical shells, yet the role of their spatial morphology in localized buckling remains insufficiently understood. This study investigates axially compressed cylindrical shells with random imperfections normalized to a common root-mean-square amplitude of A rms /t = 0.5. A total of 1600 geometrically nonlinear finite element analyses are performed for eight correlation lengths to examine the critical load factor, response localization, and imperfection–hotspot correspondence. The critical load factor varies non-monotonically with correlation length: the lowest values occur in the short-to-intermediate range, whereas the largest local roughness occurs at the shortest correlation length. Pointwise and regional analyses show that severe imperfection regions correspond most strongly with localized high-response zones over the short-to-intermediate range. Very short correlation fields exhibit rough short-wave patterns, while long correlation fields are smoother and associated with more distributed responses and weaker spatial correspondence. Within the prescribed imperfection-amplitude level, these results show that changes in spatial morphology can produce markedly different buckling responses even when the global RMS amplitude is fixed.