Instability of Metamaterial-based Thin Cylindrical Shells under Axial Compression

Abstract This paper presents comprehensive numerical studies on the instability behavior of metamaterial-based cylindrical shells (meta-shells) under axial compression. The cylindrical meta-shells are comprised of lattice-like metamaterial unit cells including house unit cells and their variants, cuboid braced, octet truss, and octahedron. Their buckling and post-buckling behavior, effects of dimensional variations, structural mass efficiency in carrying axial compression, and the influences from damaged units are studied in this work. The results show that cylindrical meta-shells can exhibit benign or multi-stable post-buckling behavior rather than catastrophic unstable post-buckling commonly seen for conventional cylindrical shells with continuous surfaces. This work finds that the critical buckling loads scale with the meta-shell dimensions following a quadratic relation. However, the meta-shells' structural mass efficiencies in carrying axial load do not change or slightly increase as their sizes proportionally increase. The study on the effects of defects shows that the critical buckling loads linearly decrease with respect to the mass of total damaged units.