Failure analysis of 1D lattice truss composite structure in uniaxial compression

To reveal compression failure modes of one-dimensional (1D) lattice truss composite structures (LTCSs), parameterized finite element modeling (FEM) method and theoretical models were developed. LTCS has four failure modes: (a) fracture of the strut; (b) global buckling; (c) shell-like buckling and (d) mono-cell buckling. Changing the bay length and the column length, buckling modes of 8-node LTCS were revealed by FEM. It is found that enough column length could induce global buckling. When the column length decreases, the failure mode will turn to shell-like buckling and mono-cell buckling or strut fracture successively. Bay length greatly influences the buckling mode. Longer bay length could change the buckling mode from global buckling or shell-like buckling directly to mono-cell buckling. Theoretical models were proposed to predict the failure loads of LTCS. Through these models, failure maps were plotted to instruct optimal designing of LTCS.