Accession Number : ADA306454

Title :   Effective Three-Dimensional (3-D) Finite Element Material Stiffness Formulation for Modeling Laminated Composites.

Descriptive Note : Final rept. Oct 90-Sep 93,

Corporate Author : ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD

Personal Author(s) : Alexander, A. ; Tzeng, J. T. ; Drysdale, W. H. ; Burns, B. P.

PDF Url : ADA306454

Report Date : APR 1996

Pagination or Media Count : 52

Abstract : A model has been developed to compute the effective properties for an element with arbitrarily shaped composite material regions. The analysis utilizes the strain energy approach and finite element technique to resolve the complexity of three-dimensional (3-D) layer geometry, anistropy, ply orientations, and multi-material regions within an element. Accordingly, the model accounts for the complex element geometries resulting from material discontinuity, changes in mesh density, and arbitrarily shaped elements that cannot be readily aligned with the layers of the laminate. The computed elastic constants are accurate, especially for the transverse shear properties. The analysis is particularly suitable for finite element applications of near-net shaped, thick-section structures. Based on the model, a pre- and postprocessor was developed to generate finite element models for computer codes such as DYNA3D and ABAQUS. Results from the finite element analysis can also be recovered to ply-by-ply basis stresses and strains.

Descriptors :   *LAMINATES, STRESS STRAIN RELATIONS, COMPUTER PROGRAMS, COMPOSITE MATERIALS, FINITE ELEMENT ANALYSIS, STRUCTURAL ANALYSIS, STIFFNESS, ELASTIC PROPERTIES, STRAIN(MECHANICS), ANISOTROPY, SHEAR STRESSES, DISCONTINUITIES, TRANSVERSE.

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE