Buckling analysis of tri-axial woven fabric composite structures subjected to bi-axial loading

The buckling behavior of several simple tri-axial woven composite structures is studied. These structures include basic tri-axial structure, modified tri-axial structure and enlarged tri-axial structure. The structure is subjected to bi-directional loading. Approximate analytical method using equivalent anisotropic plate theory is presented in this paper. Its confirmation is obtained by non-linear finite element solution. Approximate analytical method provides a simpler way to obtain the buckling load, while the non-linear finite element method gives the numerical results and detailed analysis of buckling behavior of the tri-axial structures. The non-linear finite element analysis results reveal that the structures investigated in the paper approximately have the same buckling behavior, but with different values of buckling load. When more X-crossovers are involved in the tri-axial structures, their buckling loads increase and tend to approach a certain value. The results show that techniques used for approximate analytical solution can be used to obtain the buckling load of a real life tri-axial structure. The sensitivity of the buckling behavior of the basic tri-axial structure to the change in the boundary conditions and to the imperfection due to initial configuration is investigated.