Multi-failure analyses of carbon fiber reinforced anisogrid lattice cylinders

To reveal the failure of carbon fiber reinforced composite (CFRC) anisogrid lattice cylinders, a multi-failure theory is proposed, including global buckling, local in-plane buckling, local out-of-plane buckling, Euler buckling and material failure. The global buckling is analyzed by Ritz buckling analysis through the equivalent continuum method and verified by the finite element modeling (FEM) covering different representative sizes and previous experimental results. A parametric analysis is performed to reveal the effects of the rib thickness, the rib height and the number of helical ribs and hoop ribs, on the critical load and failure modes. Failure maps are deduced to figure out the optimal route for lightweight design of the CFRC anisogrid cylinder. The theory will serve as a reference to design composite anisogrid lattice cylinders with high specific strength and stiffness.