Experimental Mechanics

, Volume 31, Issue 2, pp 111–117 | Cite as

Viscoelastic response of a unidirectional composite containing two viscoelastic constituents

  • David E. Walrath


Viscoelastic response of a unidirectional aramid fiber-reinforced epoxy was measured. Procedures to measure all five time-dependent material properties necessary to describe behavior of a transversely isotropic continuous-fiber unidirectional lamina were implemented. The Iosipescu shear method was used to measure in-plane and interlaminar shear viscoelastic response. Applicability of the Schapery single-integral nonlinear viscoelastic constitutive model to describe time-dependent mechanical behavior of a laminated composite material containing two viscoelastic phases was explored. Linear and nonlinear viscoelastic parameters for this two-viscoelastic constituent composite were measured and data summaries are presented in the paper. The time-dependent behavior of this two-viscoelastic constituent composite material was found to be complex, but the Schapery nonlinear viscoelastic model did adequately fit the response of such a composite to uniaxial applied loads.


Viscoelastic Model Viscoelastic Response Viscoelastic Parameter Unidirectional Composite Laminate Composite Material 
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Copyright information

© Society for Experimental Mechanics, Inc. 1991

Authors and Affiliations

  • David E. Walrath
    • 1
  1. 1.Department of Mechanical EngineeringUniversity of WyomingLaramie

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