Experimental Determination of Stresses in Damaged Composites Using an Electric Analogue.

Abstract

Inadequate knowledge of the local stress distributions in damaged composites has been a major obstacle to progress in the understanding of damage accumulation and ultimate failure of such materials. Theoretical treatments of 3-dimensional uniaxially reinforced composites are difficult, and direct experimental observations of stresses around interior flaws are not feasible. An experimental determination of stress distributions can be made using an electric analogue. A scaled model of the composite including the damage is made with the fibers replaced by conducting rods and the matrix replaced by an electrolyte. The resistivity ratio of rods to electrolyte is taken equal to the elastic modulus ratio of matrix to fiber. A tensile force applied in the fiber direction is modelled by applying a potential gradient in the rod direction. The displacement distribution in the composite is them modelled by the potential distribution in the analogue to an accuracy somewhat better than that given by shear lag theory. Thus stress distributions can be found by measuring potentials in the analogue with the aid of an electric probe. (Author)

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1982
Accession Number
ADA114620

Entities

People

  • Samuel B. Batdorf

Organizations

  • University of California, Los Angeles

Tags

Communities of Interest

  • C4I
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boundaries
  • California
  • Classification
  • Composite Materials
  • Differential Equations
  • Engineering
  • Equations
  • Materials
  • Mechanics
  • Military Research
  • Modulus Of Elasticity
  • Schools
  • Security
  • Shear Modulus
  • Stiffness
  • Stress Concentration
  • United States

Readers

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