Three-Dimensional Analysis for the Stress Distribution Near Circular Holes in Laminated Composites.

Abstract

A three-dimensional finite-element solution for the state of stress in a laminated composite with a circular hole, loaded in axial extension, is presented. Each layer of the laminate is assumed to be homogeneous and to have orthotropic properties. A curved isoparametric element with 24 nodal points and 72 degrees-of-freedom is used to model the individual layers of the laminate. The nodal displacements are determined by minimizing the total potential energy of the system at the element level with a conjugate gradient iterative method. Three symmetric stacking sequences ((0/90)s, (90/0)s and (- 45/+45)s) are investigated for both thick and thin boron-epoxy laminates. The results presented include inter-laminar stresses in the vicinity of a circular hole in the laminate. (Author-PL)

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1974
Accession Number
AD0783504

Entities

People

  • Jon R. Dana
  • Richard M. Barker

Organizations

  • Virginia Tech

Tags

DTIC Thesaurus Topics

  • Composite Materials
  • Displacement
  • Energy
  • Epoxy Laminates
  • Laminates
  • Materials
  • Potential Energy
  • Sequences
  • Three Dimensional

Fields of Study

  • Physics

Readers

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