Experimental Mechanics

, Volume 26, Issue 2, pp 175–184 | Cite as

The influence of fiber length and fiber orientation on damping and stiffness of polymer composite materials

  • S. A. Suarez
  • R. F. Gibson
  • C. T. Sun
  • S. K. Chaturvedi


This paper describes the theoretical analysis, the experimental results and the curve-fitting of the analytical model to the experimental results on the influence of fiber length and fiber orientation on damping and stiffness of polymer-composite materials. The experimental results show that, as predicted, very low fiber aspect ratios are required to produce significant improvements in damping. Measurements and predictions also indicate that the control of lamina orientation in a continuous fiber-reinforced laminate may be a better approach to the improvement of damping than the control of the fiber aspect ratio.


Polymer Mechanical Engineer Aspect Ratio Composite Material Fluid Dynamics 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of Symbols


complex-extensional modulus for the fiber


complex-transverse modulus for the fiber


composite extensional-complex modulus


complex modulus for the matrix


composite transverse-complex modulus


composite complex modulus along the loading direction

E′f, E″f

extensional storage and loss moduli for the fiber

E′L, E″L

extensional storage and loss moduli for the composite

E′m, E″m

extensional storage and loss moduli for the matrix


in-plane shear modulus for the composite


complex in-plane shear modulus for the anisotropic fiber


complex shear modulus for the matrix


generalized complex viscoelastic constant, or complex modulus


generalized storage modulus


generalized loss modulus

fiber length


fiber aspect ratio


effective fiber aspect ratio


composite modulusET orGLT


fiber modulusEf orGf


matrix modulusEm orGm


fiber radius


fiber-volume fraction


matrix-volume fraction


curve-fitting parameter for fiber aspect ratio


parameter defined in eq (2)


fiber-loss factor


parameters defined in eqs (6), (11) and (13)


matrix loss factor


angle of the fibers with respect to the direction of the applied load

φ1, φ2

functions defined in eq (9)


fiber Poisson's ratio


composite major Poisson's ratio

ξ, ξ1, ξ2

Halpin-Tsai parameters


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Copyright information

© Society for Experimental Mechanics, Inc. 1986

Authors and Affiliations

  • S. A. Suarez
    • 1
  • R. F. Gibson
    • 1
  • C. T. Sun
    • 2
  • S. K. Chaturvedi
    • 3
  1. 1.Mechanical Engineering DepartmentUniversity of IdahoMoscow
  2. 2.Department of Engineering SciencesUniversity of FloridaGainesville
  3. 3.Civil Engineering DepartmentOhio State UniversityColumbus

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