The elastic work factor ηel concept was applied to composite structures for the calculation of total energy release rate by using a single specimen. Cracked lap shear specimens with four different unidirectional fiber orientation were used to examine the dependence of nel on the material properties. Also, three different thickness ratios (lap/strap) were used to determine how geometric conditions affect ηel. The ηel values were calculated in two different ways: compliance method and crack closure method. The results show that the two methods produce comparable ηel values and while ηel is affected significantly by geometric conditions, it is reasonably independent of material properties for the given geometry. The results also showed that the elastic work factor can be used to calculate total energy release rate using a single specimen.
Reifsnider, K.L., E.G. Henneke and W.W. Stinchcomb .1979. "Defect Property Relationship in Composite Materials," AFML-TR-76-81, Air Force Material Laboratory, Dayton, OH: Wright-Patterson AFB, Part IV.
2.
Highsmith, A.L. and K.L. Reifsnider .1982. "Stiffness Reduction Mechanism in Composite Laminate," in Damage in Composite Materials, ASTM STP 775, American Society for Testing and Materials, pp. 103-117.
3.
Kress, G.R. and W.W. Stinchcomb .1985. "Fatigue Response of Notched Graphite/Epoxy Laminate," in Recent Advances in Composites in the United States and Japan, ASTM STP 864, American Society for Testing and Materials, pp. 173-196.
4.
Charewicz, A. and T.M. Daniel.1986. "Damage Mechanism and Accumulation in Graphite/Epoxy Laminates," in Composite Materials: Fatigue and Fracture, ASTM STP 907American Society for Testing and Materials , pp. 274-297.
5.
Whitcomb, J.D.1979. "Experimental and Analytical Study of Fatigue Damage in Notched Graphite/Epoxy Laminates,"NASA Technical Memorandum80121 .
6.
Harris, C.E. and D.H. Morris.1985. "An Evaluation of the Effects of Stacking Sequence and Thickness on the Fatigue Life of Quasi-Isotropic Graphite/Epoxy Laminate," in Recent Advances in the United States and Japan, ASTM STP 864 , American Society for Testing and Materials, pp. 153-172.
7.
Rybicki, E.F. , T.D. Herandez, Jr., J.E. Deibler, R.C. Knight and S.S. Vinson.1987. "Mode I and Mixed Mode Energy Release Rate Values for Delamination of Graphite/Epoxy Test Specimen" J. of Composite Materials , 21:105-123.
8.
Russell, A.J. and K.N. Street.1982. "Factors Affecting the Interlaminar Fracture Energy of Graphite/Epoxy Laminates,"Progress in Science and Engineering of Composites, ICCM, 4:279-286.
9.
Charentenay, F.X., J.M. Harry, Y.J. Prel and M.L. Benzeggagh .1984. "Characterizing the Effects of Delamination Defect by Mode I Delamination Test," in Effects of Defects m Composite Materials, ASTM STP 836American Society for Testing and Materials, pp. 84-103.
10.
Murri, G.B. and T.K. O'Brien.1985. "Interlaminar G IIc Evaluation of Toughened-Resin Matrix Composite Using the End-Notched Flexure Test," AIAA-85-C647, Proceedings of the 26th AIAA Spring Conference, Orlando, FL , p. 197.
11.
Gillespi, Jr., J.W., L.A. Carlsson and R.B. Pipes.1986. "Finite Element Analysis of the End Notched Flexure Specimen for Measuring Mode II Fracture Toughness,"Composite Science and Technology , 27:177-197.
12.
O'Brien, T.K. , N.J. Johnston, I.S. Raju, D.H. Morris and R.A. Simond.1987. "Comparison of Various Configurations of the Edge Delamination Test for Interlaminar Fracture Toughness," in Toughened Composite, ASTM STP 937American Society for Testing and Materials, pp. 199-221.
13.
O'Brien, T.K.1982. "Characterization of Delamination Onset and Growth in a Composite Laminate," in Damage in Composite Materials, ASTM STP 775American Society for Testing and Materials , pp. 140-167.
14.
Ramkumar, R.L. and J.D. Whitcomb.1985. "Characterization of Mode I and Mixed-Mode Delamination Growth in T300/5208 Graphite/Epoxy," in Delamination and Debonding of Materials, ASTM STP 876American Society for Testing and Materials, pp. 315-335.
15.
Johnson, W.S. and P.D. Mangalgiri .1987. "Influence of Resin on Interlaminar Mixed-Mode Fracture," in Toughened Composites, ASTM STP 937, American Society for Testing Materials, pp. 295-315.
16.
Sumpter, J.D.G. and C.E. Turner.1976. "Method for Laboratory Determination of Jc," in Cracks and Fracture, ASTM STP 601American Society for Testing and Materials, pp. 3-18.
17.
Griffith, A.A.1921. "The Phenomenon of Rupture and Flow in Solids,"Phil. Trans. Roy. Soc . , London, A.221:163-197.
18.
Irwin, G.R.1958. "Fracture,"Handbuch der Physik, 6:551.
19.
Rice, J.R.1968. "A Path Independent Integral and the Approximate Analysis of Stram Concentration at Notches and Cracks,"J. of Applied Mechanics, 35:379-386.
20.
Rice, J.R.1968. in Fracture, Vol. 2, H. Leibowitz, ed., New York: Academic Press, pp. 191-311
21.
Begley, J.A. and J.A. Landes.1972. "The J Integral as a Fracture Criterion," in Fracture Toughness, ASTM STP 514, American Society for Testing and Materials, pp. 1-23
22.
Rice, J.R., P.C. Paris and J.G. Merkle.1973. "Further Results on J-Integral Analysis and Estimates," m Progress in Flaw Growth and Fracture Toughness Testing, ASTM STP 536 pp. 231-235.
23.
Merkle, J. and H. Corten.1974. "A J-Integral Analysis for the Compact Specimen Considering Axial Force as Well as Bending Effects,"J. of Pressure Vessel Technology, Transaction,American Society of Mechanical Engineers, 96·286-292.
24.
Ernst, H.A. , P.C. Paris and J.D. Landes.1981. "Estimation on J-Integral and Tearing Modulus T from a Single Specimen Test Record," in Fracture Mechanics, ASTM STP743, pp. 476-502
25.
Dattaguru, B.R., A. Everett, Jr., J.D. Whitcomb and W.S. Johnson.1984. "Geometrically Nonlinear Analysis of Adhesively Bonded Joints,"J. of Engineering Materials and Technology , 106:59-65.
