This paper deals with the direct measurement of invariant parameters describing the intrinsic elastic response of anisotropic composite plates in bending. Theoretical results giving the link between the unknown parameters and the strain field on the top surface of a plate subjected to two different bending tests are given first. The experimental setup is then described. The invariant nature of the measured parameters is finally verified through an example. As a conclusion, it is shown that the invariant combinations of anisotropic plates compliances can be directly measured using a suitable strategy.
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References
1.
1. M.-J. Pindera and C. T. Herakovich. Shear characterization of unidirectional composite with the off-axis tension test. Experimental Mechanics, 26(1):103-112, 1986.
2.
2. F. Pierron and A. Vautrin. Accurate comparative determination of the in-plane shear modulus of T300/914 by the Iosipescu and 45 off-axis tests. Composite Science and Technology, 52:61-72, 1994.
3.
3. P. Pederson. Optimization method applied to identification of material parameters. Discretization Methods and Structural Optimization-Procedures and Applications, pages 277-283, 1989. Springer-Verlag, Berlin.
4.
4. H. Sol, H. Hua, J. De Visscher, J. Vantomme, and W. P. De Wilde. A mixed numerical/experimental technique for the nondestructive identification of the stiffness properties of fibre reinforced composite materials. NDT&E International, 30(2):85-91, 1997.
5.
5. P. S. Frederiksen. Natural vibrations of free thick plates and identification of transverse shear moduli. In Optimal Design with Advanced Materials, 48:131-148, 1993. Elsevier.
6.
6. C. M. Mota Soares, M. Moreira de Freitas, A. L. Araijo, and P. Pedersen. Identification of material properties of composite plate specimens. Composite Structures, 25:277-285, 1993.
7.
7. K.-E. Fallstrom. Determining material properties in anisotropic plates using Rayleigh's method. Polymer Composites, 12(5):306-314, 1991.
8.
8. F. Moussu and M. Nivoit. Determination of elastic constants of orthotropic constants plates by modal analysis/method of superposition. Journal of Sound and Vibration, 165(1): 149-163,1993.
9.
9. M. Grediac and P.-A. Paris. Direction identification of elastic constants of anisotropic plates by modal analysis: theoretical and numerical aspects. Journal of Sound and Vibration, 195(3):401-415, 1996.
10.
10. M. Grediac, N. Fournier. P.-A. Paris, and Y. Surrel. Direct identification of elastic constants of anisotropic plates by modal analysis: experimental results. Journal of Sound and Vibration, 210(5):645-659, 1998.
11.
11. F. Rouger, M. Khebibeche, and C. Le Govic. Non determined tests as a way to identify wood elastic parameters: the finite element approach. Proc. of Euromech Colloquium 269 Mechanical Indentification of Composites, pages 82-90, 1990. Elsevier.
12.
12. M. A. N. Hendricks. Identification of the mechanical properties of solid materials. Doctoral dissertation, Eindhoven University of Technology, 1991.
13.
13. G. Bezine and G. Shi. A new method for the determination of the flexural rigidity of an orthotropic plate. Engng. Anal. Boundary Elements, 10:307-312, 1992.
14.
14. M. Grddiac and A. Vautrin. A new method for determination of bending rigidities of thin anisotropic plates. Journal of Applied Mechanics, 57:964-968, December 1990. Transactions of the American Society of Mechanical Engineers.
15.
15. M. Grediac and A. Vautrin. Mechanical characterization of anisotropic plates: experiments and results. European Journal of Mechanics/A Solids, 12(6):819-838, 1993.
16.
16. S. W. Tsai and H. T. Hahn. Introduction to Composite Materials. Technomic, 1980.
17.
17. N. Kandil and G. Verchery. Some new developments in the design of stacking sequences of laminates. Proceedings of the Seventh International Conference on Composite Materials, 3:358-363, 1988. Pergamon Press.
18.
18. E. M. Wu, K. L. Jerina, and R. E. Lavengood. Data averaging of anisotropic composite material constants. ASTM, 521:229-252, 1973.
19.
19. M. Grddiac, A. Vautrin, and G. Verchery. A general method for data averaging of anisotropic elastic constants. Journal of Applied Mechanics, 60:614-618, 1993. Transactions of the American Society of Mechanical Engineers.
20.
20. B. Gommers, I. Verpoest, and P. Van Houtte. Determination of the mechanical properties of composite materials by tensile tests. Part 1: elastic properties. Journal of Composite Materials, 32(4): 310-334, 1998.
21.
21. M. Grediac. On the direct determination of invariant parameters governing anisotropic plate bending problems. International Journal of Solids and Structures, 33(27):3969-3982, 1996.
22.
22. S. G. Leknitskii. Anisotropic Plates. Gordon and Breach Science Publishers, 1968.
23.
23. ISO NWI 465. Reinforced plastics-determination of in-plane shear modulus by the plate twist method, 1995.
24.
24. O. Kafri and L. Glatt. High-sensitivity reflection-transmission moire deflectometer. Applied Optics, 27(2):351-353, 1988.
25.
25. W. Omura and T. Yatagai. Phase measuring Ronchi test. Applied Optics, 27(3):523-528, 1988.
26.
26. D. Malacara. Analysis of the interferometric Ronchi test. Applied Optics, 29(25):3633-3637, 1990.
27.
27. A. Assa, J. Politch, and A. A. Betser. Slope and curvature measurement by a double-frequency-grating shearing interferometer. Experimental Mechanics, 19(4): 129-137, 1979.
28.
28. N. Fournier, M. Grddiac, P.-A. Paris, and Y. Surrel. Phase-stepped deflectometry applied to shape measurement of bent plates. Experimental Mechanics, 1997. Accepted for publication.
