Strength of laminated composites with internal discontinuities parallel to the applied load

Abstract

A quasi-three-dimensional finite element analysis is used to determine the state of stress at and near the internal discontinuity. Two techniques to predict the strength are developed. In one technique, the state of stress in a small resin pocket at the discontinuity is used with an isotropic failure criterion to determine the strength of the discontinuity. The other technique uses the in-plane state of stress around the discontinuity with a failure criterion based on an analogy with an individual ply