Abstract
The composite material have been finding ever increasing applications in aerospace, vehicle and marine structures, electronic packaging, armour safety device, and sporting goods. Composites, made of reinforcement fibers and matrix, are anisotropicin mechanical properties. Three-dimensional elasticity is a necessity in a good mechanics analysis. Since the stiffness differs in each direction from layer to layer, layerwise displacements must be assumed, in which stresses and strains are independent in the individual layers from a micro-point of view. However, the transverse stressσzz,σyz,σxz and the 3-D displacements u, v, w must be continue at the layer interfaces. In the linear/nonlinear theories six types of Lagrange multipliers are used to implement the interlaminar continuity and lateral surface conditions in addition to the various potentials via the augmented 3-D energy variational approach and dynamic governing equations are set up for solutions to the associate problems. In the large deformation elastic analysis, von Karman finite strains are adopted by using the linear strain as an initial guess. Starting from the linear theory of free vibration for laminated rectangular plates and doubly curved panels, on 3 types of 3-D simple supports this dissertation conclude with nonlinear stress analysis, prediction of first-ply failure of the various thick and thin laminated plates on four types of clamped edge conditions. Numerical results are reasonable in comparison with existing literature, especially experiments.