A General Three-Dimensional Computational Model for Nonlinear Composite Structures and Materials.

Abstract

A computational model for the analysis of structural and microstructural behavior in general solids of composite material is presented. Emphasis is placed on representing the anomalous material behavior of composites and on the construction of computational models with variable properties. Alternative material models using continuum and statistical mechanics were reviewed and a modular code designed for compatibility with several different models. The constituent materials are characterized in terms of those state variables that correlate a materials response such as effective stress or strain energy. A parametric cubic representation is used for all state variables, the solid geometry and all physical properties. The associated finite element extends isoparametric modeling to allow properties, linear or nonlinear, to vary over the volume of an element as in rosette material construction. Applications of the model to a carbon-carbon unit cell, to strain singularities and to the inelastic response of a graphite bar illustrate its utility. Good agreement with triaxial test data for inelastic strains under hydrostatic pressure is obtained. Numerical results are computed using PATCHES-III and the conjugate gradient algorithm without the assembly of large matrices. This approach is tailored for vector processors and can reduce the high cost of nonlinear three-dimensional analyses. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1977
Accession Number
ADA041413

Entities

People

  • Edward L. Stanton

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Ground and Sea Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Applied Mechanics
  • California
  • Composite Materials
  • Crystal Structure
  • Engineering
  • Engineers
  • Gages
  • Lymphocytes
  • Materials
  • Mechanical Properties
  • Mechanics
  • New York
  • Parallel Computing
  • Parallel Processing
  • Physical Properties
  • Stresses
  • Three Dimensional

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Mechanical Engineering/Mechanics of Materials.
  • Structural Health Monitoring of Composite Structures.