Accession Number:

AD0783504

Title:

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

Descriptive Note:

Interim rept.,

Corporate Author:

VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG DEPT OF ENGINEERING SCIENCE AND MECHANICS

Personal Author(s):

Report Date:

1974-08-01

Pagination or Media Count:

42.0

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 090s, 900s and - 4545s 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

Subject Categories:

  • Laminates and Composite Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE