ISSN: 0884-6804
CODEN: JCTRER
Page Count: 6

Predictions of Poisson's Ratio in Cross-Ply Laminates Containing Matrix Cracks and Delaminations
Harris, CE
Branch head, Mechanics of Materials Branch, NASA Langley Research Center, VA

Allen, DH
Professor and graduate assistant, Texas A&M University, TX

Nottorf, EW
Professor and graduate assistant, Texas A&M University, TX

Abstract

A damage-dependent constitutive model for laminated composites has been developed for the combined damage modes of matrix cracks and delaminations. The model is based on the concept of continuum damage mechanics and uses second-order tensor valued internal state variables to represent each mode of damage. The internal state variables are defined as the local volume average of the relative crack face displacements. Since the local volume for delaminations is specified at the laminate level, the constitutive model takes the form of laminate analysis equations modified by the internal state variables. Model implementation is demonstrated for Ex and vxy of quasi-isotropic and cross-ply laminates. The model predictions are in close agreement to experimental results obtained for graphite/epoxy laminates.

Keywords:
continuum damage mechanics, matrix cracks, delaminations, graphite/epoxy

Paper ID: CTR10152J
DOI: 10.1520/CTR10152J
ASTM International is a member of CrossRef.