Accession Number : ADP002977

Title :   Finite Element Analysis of Fabrics with Nonlinear Stress-Strain Laws,

Corporate Author : ARMY MATERIALS AND MECHANICS RESEARCH CENTER WATERTOWN MA

Personal Author(s) : Johnson,A. R.

Report Date : FEB 1984

Pagination or Media Count : 20

Abstract : The material constitutive relationships for woven fabrics are nonlinear. This, together with the fact that transversely loaded fabric membranes undergo large deformations, presents a difficult analysis problem to designers using fabrics in structures. In this effort, the constant strain triangular element is used for the development of finite element gradient and tangent matrices for the case when the material energy density functional is a Constant squared function of the warp and fill strains. The element matrices are derived using the nonlinear Green strain-displacement relations to describe the warp and fill strains in terms of the deformations of the fabric. Biaxial stress-strain data for a 2.6 oz/sq ud cotton cloth is used to obtain approximate stress-strain functionals and an energy density functional. The element is used to determine the deformations and stresses in a uniformly loaded square fabric membrane. (Author)

Descriptors :   *Stress strain relations, *Cotton textiles, Deformation, Finite element analysis, Gradients, Displacement, Matrices(Mathematics), Stress analysis, Loads(Forces), Biaxial stresses, Exponential functions, Membranes, Inflatable structures

Distribution Statement : APPROVED FOR PUBLIC RELEASE