Application of the Quadric Surfaces Criterion to Laminated Composites Containing a Through Thickness Crack

The purpose of this study is to apply the newly developed quadric surfaces failure criterion to laminated composites containing stress concentrations under tensile loading. To investigate this criterion, the influence of the material anisotropic properties and the far-field loading on the Graphite/Epoxy [90/0 /45] _s laminates with a central crack were studied. The fracture angle and damage zone can also be evaluated from this criterion. The tensile failure of a laminate is governed by the failure of the plies having fibers parallel to the loading direction. Under the uniaxial tensile load, the fracture planes of all the plies are perpendicular to the tensile loading direction within the [90/0 /45] _s laminates containing a central crack.