| This study was separated into two components.;In the first component, cyclic loading of cross-ply and multi-ply specimens was examined. (02/903), and (+/-45/903)s laminates were tested under quasi-static and cyclic loading. Damage curves for crack initiation, delamination initiation, and final failure were developed. Visual damage growth, transverse crack growth, and stiffness reduction measurements were examined to determine how and why damage grew throughout the specimens.;In the second component, constrained angle ply specimens were examined. Laminates with orientations of (0/+/-theta4/0)T where theta = 25, 45, and 75 degrees were tested under monotonic and cyclic loading. For these specimens damage curves for crack initiation, crack saturation, and delamination initiation were developed. Visual damage growth was compared with stiffness reduction measurements and correlations were observed between the two. Visual damage was examined using a microscope to examine the edges, and an image processor to examine through the width of the specimen. |
