Elastodynamic Response of a Unidirectional Composite Laminate to Concentrated Surface Loads: Part I

Abstract

The quantitative features of the elastodynamic field produced in a unidirectional graphite/epoxy composite laminate by surface loads are studied. The material of the composite is modeled as a transversely isotropic dissipative medium with its symmetry axis parallel to the laminate surface. The surface displacement produced by a transient concentrated point load on the surface of a uniform half-space and a plate of finite thickness is calculated by means of a multiple transform technique followed by inversion through numerical integration. The two-dimensional (plane-strain) line load problems for the plate are also solved as special cases. In addition, an approximate solution based on the classical plate bending theory which includes transverse shear and rotary inertia is obtained and the range of validity of the approximate solution is determined through comparison with the exact results. The multiple transform technique is shown to be a viable alternative to finite element and other numerically intensive computational schemes for wave field calculations in composite laminates. Part I of the paper contains the formulation, and a discussion of the general features of the response, the numerical treatment and results are given in Part II.