Experimental Mechanics

, Volume 30, Issue 4, pp 345–351 | Cite as

Strain and stress concentrations in composite laminates containing a hole

  • S. C. Tan
  • R. Y. Kim


The strain concentrations of orthotropic composite laminates containing a circular hole and subject to tensile loading were measured experimentally using strain gages. Then the stress concentrations were calculated using the strain distributions in the initial region of the stress-strain curve before any microdamages were developed. The graphite/epoxy AS4/3502 [O2/±45]2s and [45]4s were chosen to represent fiber-dominated and matrix-dominated laminates, respectively. Several combinations of hole-diameter/plate-width ratio were designed to show the width effect. The conditions of the laminates, after the holes were drilled, were examined using X-ray techniques. Good correlation was obtained between theory and experimental result using specimens in good condition (without machining damages). A procedure for accurately determining the strain and stress concentrations is given.


Mechanical Engineer Fluid Dynamics Stress Concentration Good Condition Strain Gage 
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  1. 1.
    Dally, J.W. and Riley, W.F., Experimental Stress Analysis, 2nd Ed., McGraw-Hill (1978).Google Scholar
  2. 2.
    Whitney, J.M. andNuismer, R.J., “Stress Fracture Criteria for Laminated Composites Containing Stress Concentrations,”J. Comp. Mat.,8,253–265 (1974).Google Scholar
  3. 3.
    Tan, S.C., “Laminated Composites Containing an Elliptical Opening. I. Approximate Stress Analyses and Fracture Models,”J. Comp. Mat.,21,925–948 (Oct. 1987).Google Scholar
  4. 4.
    Rowlands, R.E., Daniel, I.M. and Whiteside, J.B., “Stress and Failure Analysis of a Glass-Epoxy Composite Plate with a Circular Hole,” Experimental Mechanics,31–37 (Jan. 1973).Google Scholar
  5. 5.
    Daniel, I.M., Rowlands, R.E. and Post, D., “Strain Analysis of Composites by Moiré Methods,” Experimental Mechanics,246–252 (June 1973).Google Scholar
  6. 6.
    Tan, S.C., “Finite-Width Correction Factors for Anisotropic Plate Containing a Central Opening,”J. Comp. Mat.,22,1080–1097 (Nov. 1988).Google Scholar
  7. 7.
    Tan, S.C., “Mixed-Mode Fracture of Notched Unidirectional and Off-Axis Laminates Under Tensile Loading,”J. Comp. Mat.,23,1082–1105 (Aug. 1989).Google Scholar
  8. 8.
    Kim, R.Y., “Experimental Observation of Free-edge Delamination Interlaminar Response of Composite Materials,” ed. N.J. Pagano, Elsevier (1989).Google Scholar
  9. 9.
    Tan, S.C., “Mixed-Mode Fracture of Notched Composite Laminates under Uniaxial and Multiaxial Loading,”Eng. Fract. Mech.,31,733–746 (1988).Google Scholar

Copyright information

© Society for Experimental Mechanics, Inc. 1990

Authors and Affiliations

  • S. C. Tan
    • 1
  • R. Y. Kim
    • 2
  1. 1.Wright Patterson AFB
  2. 2.University of Dayton Research InstituteDayton

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