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Analytical-experimental correlation of polyaxial states of stress in Thornel-epoxy laminates

Predicted and observed biaxial stress-strain response and strength of [O2/±45] s Thornel-epoxy composites are compared

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Abstract

The observed strength and stress-strain response of [O2/±45] s Thornel-epoxy laminates under varying biaxial-stress ratios are compared with those predicted numerically. Both flat and ring-type off-axis composite specimens are employed by which to generate experimentally the biaxial data. While the numerical predictions tend to overestimate the observed laminate strengths, the several predicted stress-strain curves agree well with each other and with experiment. The off-axis ring specimens produced significantly higher strengths than did the corresponding flat specimens.

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Abbreviations

σ, τ:

stresses

ε, γ:

strains

E :

elastic modulus

G :

shear modulus

ν:

Poisson's ratio

S ij :

compliance

1, 2:

lamina axes of material symmetry

x, y :

laminate axes of material symmetry

x′,y′ :

rotated coordinate system

X, Y, S :

principal lamina tensile normal and shear strengths

X*, Y*, S* :

principal lamina compressive normal and shear strengths

u :

denotes ultimate value as a subscript or superscript

θ:

off-axis angle

K 1,K 2,K 6 :

coefficients

References

  1. Tsai, S.W., “Strength Characteristics of Composite Materials,” NASA CR-224 (Apr. 1965).

  2. Tsai, S.W. andWu, E.M., “A General Theory of Strength for Anisotropic Materials,”J. Comp. Mats.,5 (1),58–80 (Jan.1971).

    Google Scholar 

  3. Wu, E.M., “Optimum Experimental Measurements of Anisotropic Failure Tensors,”J. Comp. Mats.,6 (4),472–489 (Oct.1972).

    MATH  Google Scholar 

  4. Petit, P.H. andWaddoups, M.E., “A Method of Predicting the Nonlinear Behavior of Laminated Composites,”J. Comp. Mats.,3 (1),2–19 (Jan.1969).

    Google Scholar 

  5. Sandhu, R.S., “Ultimate Strength Analysis of Symmetric Laminates,”Wright-Patterson AFB, OH, AD779927 AFFDL-TR-137 (Feb. 1974).

    Google Scholar 

  6. Sandhu, R.S., “Nonlinear Response of Unidirectional and Angle-Ply Laminates,” AIAA Paper No. 74-380 presented 15th AIAA-ASME Structural Dynamics and Materials Conference, Las Vegas, NV (Apr. 1974).

  7. Sendeckj, G.P., Richardson, M.D. andPappas, J.E. “Failure Behavior of Thornel-300/5208 Epoxy Laminates,”Wright-Patterson AFB, OH, Tech. Rep. AFFDL-TR-74-89-FBC (Apr. 1974).

    Google Scholar 

  8. Yeo, Y.T. andBrinson, H.F., “An Experimental Investigation on the Tensile Moduli and Strengths of Graphite/Epoxy Laminates,”Experimental Mechanics,17 (11),401–408 (Nov.1977).

    Google Scholar 

  9. Rowlands, R.E., “Flow and Failure of Biaxially Loaded Composites,” Inelastic Behavior of Composite Materials, ASME-AMD,13,97–125 (Dec.1975).

    Google Scholar 

  10. Cole, B.W. andPipes, R.B., “Filamentary Composite Laminates Subjected to Biaxial Stress Fields,”Wright-Patterson AFB, OH, AD785362, AFFDL-TR-73-115 (Jun. 1974).

    Google Scholar 

  11. Rowlands, R.E., “Analytical-Experimental Correlation of the Biaxial States of Stress in Composite Laminates (T/300-5208),”Wright-Patterson AFB, OH, Tech. Rep., AFFDL-TR-75-11 (Apr.1975).

    Google Scholar 

  12. Petit, P.H., “A Simplified Method of Determining the Inplane Shear Stress Strain Response of Unidirectional Composites,” Composite Materials Testing and Design, ASTM,ASTM STP 460,83–93 (1969).

    Google Scholar 

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Authors and Affiliations

  1. Department of Engineering Mechanics, University of Wisconsin-Madison, 53706, Madison, WI

    Robert E. Rowlands (Associate Professor)

Authors
  1. Robert E. Rowlands
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Rowlands, R.E. Analytical-experimental correlation of polyaxial states of stress in Thornel-epoxy laminates. Experimental Mechanics 18, 253–260 (1978). https://doi.org/10.1007/BF02324166

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  • DOI: https://doi.org/10.1007/BF02324166

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