STRESS ANALYSES OF COMPOSITE LAMINATE WITH DELAMINATION USING X-FEM

The extended finite element method (X-FEM) is applied to the stress analysis of composite laminates having interlaminar planar delamination. In X-FEM analysis, the geometry of such delaminations can be modeled independent of the finite elements. The domain form of the contour integral can be used to compute the energy release rate in conjunction with X-FEM. As numerical examples, three-dimensional analyses for DCB and ENF test specimens were performed by X-FEM with various enrichment nodes, and the obtained results were examined. In addition, a model of the no-friction-contact condition by X-FEM was proposed and applied to ENF test analysis. Moreover, eigenvalue buckling analyses of a CFRP plate with delamination were performed by X-FEM as a practical example related to Compression After Impact (CAI) problems of composite materials. The numerical results show that X-FEM is an effective method for analyzing stress in composite laminates with delamination.