Accession Number:

ADA160433

Title:

Three-Dimensional Stress Singularities in Anisotropic Materials and Composites.

Descriptive Note:

Final rept. 15 Mar 83-15 Aug 84,

Corporate Author:

ILLINOIS UNIV AT CHICAGO CIRCLE

Personal Author(s):

Report Date:

1985-08-01

Pagination or Media Count:

65.0

Abstract:

A general numerical procedure is presented for determining the 3-dimensional stresses singularities in anisotropic materials and composites. The geometry near the singular point can be represented by a conical wedge whose lateral surface is generated by straight lines passing through the wedge apex. The shape S sub 1 of the cross section of the conical wedge at any constant radial distance defines the geometry of the 3-dimensional singular point in the material. If S sub 1 consists of two regions each occupied by a different material, we have a 3-dimensional composite conical wedge. A finite element scheme based on variational principles is used to find the order of stress singularities at the wedge apex. The method can be applied to any shape of S sub 1. Several examples are presented. For comparisons with the existing numerical schemes for isotropic materials, the method is applied to special geometry and to isotropic materials. It is shown that the 8 node higher order isoparametric elements employed here is very efficient in obtaining a fairly accurate result. Keywords Elasticity Stress intensity Eigenvalues Eigenfunctions Anisotropy Composite materials Three dimensional.

Subject Categories:

  • Laminates and Composite Materials
  • Theoretical Mathematics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE