Three-dimensional finite element analysis was used to study cross-ply laminates with a delamination near the intersection of orthogonal ply cracks. Three lami nates were studied: (0/90)s, (90/0)s, and ((0/90)s)∞ . Mode mix was sensitive to stacking sequence, location along the delamination front, and delamination shape and size. The mode III component was generally the largest component. For loading in the x-direction, there were extremely strong gradients of GI and GIII near the yz-plane, where the delami nation front intersected a ply crack.
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