Date of Award


Document Type


Degree Name

Master of Science in Aeronautical Engineering


Department of Aeronautics and Astronautics

First Advisor

Anthony N. Palazotto, PhD


This study involved a numerical and experimental investigation of the (geometric instability of graphite/epoxy cylindrical panels with free vertical edges undergoing axial compression. Symmetric quasi-isotropic laminates with five different size centralized cutouts, were investigated for two axial lengths of panels and three thicknesses. The study compared experimental data to results from SHELL, a geometrically nonlinear finite-element program which incorporates a parabolic transverse shear strain distribution through the thickness. The research verified that the SHELL program will provide good predictions of the collapse characteristics of a panel with large cutouts of varying dimensions undergoing large displacements and rotations. The best correlation between the numerical and experimental results occurred for 16 ply panels in comparison to 8 and 24 ply panels. The variation between these results is attributed to panel curvature, material, and geometric imperfections. This study verified that cutout dimensionality effects the panel transverse shear strain, which in turn effects the panel collapse load. In addition, this research conducted parametric studies to determine one dimensional models that could be used in lieu of SHELL to estimate collapse loads from a known solution for panel with geometric variations from the known panel solution.

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The author's Vita page is omitted.