Prediction of Tensile Matrix Failure in Composite Laminates

A conceptually simple mixed mode fracture analysis method is presented for the prediction of tensile matrix failure in composite laminates. The analysis technique, which makes use of a mixed mode strain energy release rate fracture criteria in con junction with an approximate two-dimensional shear-lag model, is cast in terms of a tensile matrix strength criterion. In contrast to presently available point stress tech niques, surprisingly accurate predctions of mode I matrix failure in the 90° lamina of (±θ/90 n ) s and mixed mode matrix failure in the θ° lamina of (0 2 /θ) s T300/934 com posite laminates are observed.