Statistical analysis of the progression of transverse cracking and delamination in cross-ply laminates

The paper presents a statistical analysis of the transverse cracking and delamination process induced in cross-ply laminates subjected to tensile loading. First, the paper considers the initiation and progression of transverse cracking. This progression is evaluated by an iterative procedure combining a generalized model for evaluating the stress field in a cracked laminate with a statistical distribution of strengths in the 90° layer. Comparisons between the results obtained by this procedure and the experimental results of the literature show that for very low crack densities the progression of transverse cracking is governed by a strength distribution associated with weakness areas resulting from the presence of particular defects in laminates. Next, for higher crack densities the strength distribution in the 90° layer can be described by a pseudo-normal distribution associated with the other defects. Finally, the paper considers the development of delamination which is initiated from the crack tips in the case of some laminates.