3-DIMENSIONAL EFFECTIVE PROPERTIES OF COMPOSITE-MATERIALS FOR FINITE-ELEMENT APPLICATIONS

A model has been developed to compute the effective properties for an arbitrarily shaped element with multiple anisotropic material regions. The analysis utilizes a finite element technique to resolve the compl exity of three-dimensional layer geometry, anisotropy, ply orientation s, and multi-material regions within an element. Accordingly, the mode l accounts for complex geometries requiring changes in mesh density an d/or arbitrarily shaped elements that cannot be readily aligned with t he layers of the laminate. Discontinuity due to ply drop-off or layer terminations within an element is also considered. The computed elasti c constants are accurate, especially for the transverse shear properti es. The analysis is particularly suitable for finite element applicati ons of near-net shaped thick-section structures. A preprocessor was de veloped incorporating the effective property model to allow for genera tion of finite element representations for computer codes such as DYNA 3D and ABAQUS.