A quasi-three-dimensional finite element analysis of a symmetric angle-ply [+454/-454]s laminate subjected to a uniform axial extension was conducted and the results compared with experimental data generated for this purpose. Singular finite elements were embedded around the interface/free edge and eight-noded quadrilateral elements were used elsewhere. The order of the singularity was obtained from a closed form elasticity solution. The order to the singularity compared well will those in previous published numerical analyses. The analyses predicted the presence of high interlaminar normal and shear strain concentrations along the free edge. The results were compared to experimental data obtained using the moiré interferometric technique. The experimental data consist of displacement patterns and an interlaminar normal strain concentration along the free edge. Favorable agreement between analysis and experiment is obtained only if the singular element is embedded in a small region around the singular point. Supported by a detailed literature review, the agreement between the analysis and the experimental data shows that a quasi-three-dimensional analysis is sufficiently accurate.
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