FREE-EDGE EFFECTS IN UNSYMMETRICALLY LAMINATED COMPOSITE PLATES

The free-edge effect in unsymmetrically laminated plates subjected to a uniformly distributed tensile force or bending moment is studied. A variational asymptotic formulation, leading to a finite element scheme in the free-edge layer, is presented. A stress field is determined for symmetric and unsymmetric laminates subjected to tension and bending loadings. Based on two criteria, the edge effect is compared between the different sample cases. It is found that the edge effect is more dominant in tension than in bending loading for symmetric and unsymmetric laminates, and more pronounced for symmetric angle-ply than for unsymmetric angle-ply laminates.