Generalized quasi-three dimensional analysis of composite laminates with unsymmetrically located free-edge delaminations

This paper presents a generalized quasi-three dimensional (GQ3D) analysis of composite laminates with delamination. Two techniques are developed for the analysis: one is a generalized quasi-three dimensional finite element method (GQ3D-FEM), and the other is a generalized quasi-three dimensional classical laminated plate theory (GQ3D-CLT). The GQ3D analyses are performed on [30₂/-30₂/90[_S laminates subjected to uniaxial extension, with free-edge delaminations located unsymmetrically with respect to the laminate midplane. The results obtained by the two techniques reveal bending deformations and twisting deformations of the laminates, and increasing energy release rates as the delamination growth. The differences of the generalized quasi-three dimensional analysis from the quasi-three dimensional analysis are also clarified.