Recent Biaxial Test Results of Laminated Composites and Analytical MCT Predictions

Abstract

As the use of advanced composite materials continues to expand into new technology areas, a troublesome issue arises involving the inability of mainstream designers to accurately predict the initiation and growth of the material damage under multiaxial stress states. This shortcoming was clearly illustrated in impressive fashion under the recent "World Wide Failure Exercise". The inability to predict the load response of composite materials in the region of their ultimate load has been primarily attributed to both incomplete development of a general composite failure theory and insufficient multiaxial experimental data for verification. To this end, an ongoing analytical and experimental effort was pursued by the authors. A thickness-tapered cruciform specimen was developed and shown to be capable of producing acceptable multiaxial results for specific composite laminate architecture. The electromechanical test facility at the Air Force Research Laboratory, Space Vehicles Directorate, is capable of generating any combination of tensile or compressive stresses in sigma(sub1):sigma (sub2):sigma(sub3) stress space. To date, biaxial tests and numerical predictions were performed on two laminate stacking sequences, cross-ply and quasi-isotropic, and two material systems, carbon/epoxy and E-glass/vinyl ester. The results between analytical predictions generated using Multicontinuum Theory (MCT) will be correlated with multiaxial experimental results providing further insight to the capabilities of the current experimental approach.

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Document Details

Document Type
Technical Report
Publication Date
Nov 18, 2004
Accession Number
ADA430655

Entities

People

  • J. S. Mayes
  • Jeffry S. Welsh

Organizations

  • Alfred University

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Composite Materials
  • Engineering
  • Experimental Data
  • Geometry
  • Laminates
  • Materials
  • Mechanical Engineering
  • Military Research
  • Spacecraft
  • Test Facilities
  • Test Methods
  • Thickness
  • Three Dimensional
  • Two Dimensional
  • United States

Readers

  • Structural Health Monitoring of Composite Structures.
  • Systems Analysis and Design

Technology Areas

  • Microelectronics
  • Space