Strength analysis of composite grid stiffened structure

Composite grid stiffened structure is made up of continuous fiber wound oblique ribs, hoop ribs and skin. Through further development of FEM calculation software ANSYS, the skin and ribs are simulated by laminated plate elements and beam elements. According to the geometrical characteristics of composite grid stiffened structure and distribution of the load on it, cyclic symmetry finite element model is established. And based on the max-stress criterion, max-strain criterion, Tsai-Wu failure criterion and Chang stiffenss degradation criterion, the strength of the structure under the axial load is predicted and analyzed during failure processes. The calculation results based on Tsai-Wu failure criterion and Chang stiffness degradation criterion show a good agreement with the test results.