This study is a dimensional analysis of the shell-like buckling failure mode of 8-node IsoTruss® structures, composite lattice grid columns, subject to uniaxial compression. The specimens analyzed herein are composed of graphite/epoxy materials and were designed in a preceding study for light-weight space applications, being approximately 3 m (10 ft.) long and 0.14 kg (0.31 lb.). Buckingham's Pi Theorem is implemented to reduce the critical geometric and material design parameters to a smaller set of independent, non-dimensional Π variables. The shell-like buckling load is also made non-dimensional and assigned as the dependent Π variable. Finite element analyses are performed to predict the shell-like buckling loads of various configurations of IsoTruss structures. The predicted shell-like buckling loads are plotted in the form of Π variables with respect to design parameters to characterize trends. The finite element predictions are also plotted with analytical predictions to evaluate the accuracy of an analytical expression derived in a preceding study. Results indicate that the analytical expression accurately represents the influence of the longitudinal radius and bay length, however, the stiffness contributed by the helical radius is underestimated.
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