Viscoelasticity of Axisymmetric Composite Structures: Analysis and Experimental Validation

Abstract

Stress relaxation and creep of composite cylinders are investigated based on anisotropic viscoelasticity. The analysis accounts for ply-by-ply variation of material properties, ply orientations, and temperature gradients through the thickness of cylinders subjected to mechanical and thermal loads. Experimental validation of the model is conducted using a high tensioned composite overwrapped on a steel cylinder. The creep and stress relaxation response of composite is accelerated at elevated temperatures, then characterized and compared with the model simulation. Fiber-reinforced composite materials generally illustrate extreme anisotropy in viscoelastic behavior. Accordingly, viscoelastic characteristics of composite cylinders are quite different from those of isotropic cylinders. Viscoelastic effects of the composite can result in a drastic change of stress and strain profiles in the cylinders over a period of time, which is critical for structural durability of composite cylinders. The developed analysis can be applied to composite pressure vessels, gun barrels, and flywheels.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 2013
Accession Number
ADA576156

Entities

People

  • Daniel J. O'brien
  • Jerome T. Tzeng
  • Ryan P. Emerson

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Energy and Power Technologies
  • Ground and Sea Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Axisymmetric
  • Carbon Fibers
  • Climate Change
  • Composite Materials
  • Composite Structures
  • Constitutive Equations
  • Epoxy Composites
  • Equations
  • Fiber Reinforced Composites
  • Graphitic Materials
  • Gun Barrels
  • Materials
  • Military Research
  • Orientation (Direction)
  • Pressure Vessels
  • Radial Stress
  • Simulations

Readers

  • Structural Dynamics.
  • Structural Health Monitoring of Composite Structures.