Elastic moduli of laminated anisotropic composites

The present investigation is concerned with the development of a theoretical basis for determining the elastic moduli of laminated anisotropic materials within the framework of the theory of plates and shells, and the establishment of sound experimental procedures for the confirmation of the predicted results. A general theory is formulated whereby the properties of a laminated anisotropic composite can be predicted once the material properties, the thickness and the orientation of each unit ply are known. Treated in detail are the cross-ply and angle-ply laminates, these configurations being of increasing importance to designers and analysts of filament-wound materials. Laminated materials of this type may, depending on lamination parameters, exhibit coupling between in-plane strain and bending or twisting curvature which must be considered in the analysis and testing of such materials. Based on an understanding of the predicted mechanical behavior, an experimental program is designed, using glass-filament-reinforced resin cross-ply and angle-ply plates and cylindrical pressure vessels as test specimens, which confirms the validity of the theory and presents experimental data heretofore not available.