Buckling Stability of Additively Manufactured Isogrid

This work investigated the buckling stability of isogrid panels manufactured using fused deposition modelling (FDM). In particular, it verified the use of existing closed form analytical solutions and finite element analyses for predicting both global and local buckling loads and modes for these structures. FDM-produced isogrid samples were subjected to uniaxial quasi-static compression with boundary conditions approximating simple supports. Buckling values and mode shapes were obtained from Digital Image Correlation (DIC). The values obtained experimentally were compared to buckling loads calculated using finite element analysis and closed form solutions for orthotropic materials. Good agreement was obtained in comparing finite element analysis to experimental results for both global and local modes, while closed-form solutions compared well for the global modes for which the solutions were intended.