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Abstract

A stochastic mesomechanics model has been developed for damage accu mulation analysis in advanced laminated composites. The model is based on a theory of excursions of random process beyond the bounds. Stochastic strains in the laminate sub jected to random Gaussian inplane loading are calculated using lamination theory and random functions theory. Probabilistic variation of stiffness and strength characteristics of plies is used in the analysis. A stochastic version of the maximum strain failure criterion is applied for damage probability calculation. A mesovolume concept is utilized in model ing stiffness degradation. The capabilities of the model are illustrated by predictions of damage accumulation and failure in a Kevlar®/epoxy [0/ 4 30/90]. laminate under quasi stationary, longterm stationary, and cyclic loading. Effects of loading rate, deviation, sta tionary level, and cyclic amplitude on damage evolution are discussed. Inversion of the in fluence of loading deviation on laminate strength with varying loading rate is revealed and interpreted. Highcycle fatigue behavior of the laminate is calculated utilizing the observed stages in failure accumulation under cyclic loading.

References

1. Wagner, H. D. 1989. "Statistical Concepts in the Study of Fracture Properties of Fibres and Com posites," Composite Materials Series. Vol. 6 Application of Fracture Mechanics to Composite Materials, K. Friedrich , ed., Elsevier, pp. 39-77.

2. Argon, A. 1974. "Statistical Aspects of Fracture," Composite Materials. Vol. 5, Fracture and Fa tigue, Academic Press. pp. 166-205.

3. Stock, T. A. , P. X. Bellini , L. N. Murthy and C. C. Chamis . 1988. "Probabilistic Composite Micromechanics," 29th Structure, Structural Dynamics and Materials Conference. Part 3. Wil liamsburg, Virginia.

4. Ovchinskii, A. S. 1988. Fracture Processes in Composite Materials: Computer Simulation of Micro and Macro-Mechanisms. Moscow: Nauka (in Russian).

5. Dzenis, Y. A. , S. P. Joshi and A. E. Bogdanovich . 1992. "Damage Evolution Modeling in Ortho tropic Laminated Composites," 33rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Material Conference, April 13-15, Dallas: Part 5, pp. 2887-2897 (accepted for publication in AIAA Journal).

6. Dzenis, Y. A. , S. P. Joshi and A. E. Bogdanovich . 1992. "Damage Evolution Analysis of Lami nates Subjected to Random Quasistatic Loading," 7th ASC Technical Conference on Composite Materials, October 13-15, University Park, Pennsylvania, pp. 1084-1093.

7. Dzenis, Y. A. , S. P. Joshi and A. E. Bogdanovich . 1993. "Behavior of Laminated Composites under Monotonically Increasing Random Load," AIAA Journal, 31:2329-2334.

8. Dzenis, Y. A. , and S. P. Joshi . 1993. "Long-Term Strength and Damage Accumulation in Laminates," 34th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Material Conference, April 19-21, La Jolla, California: Part 4, pp. 1873-1880.

9. Dzenis, Y. A. and S. P. Joshi and A. E. Bogdanovich . 1993. "Damage Analysis of Laminates Under Cyclic Loading," International Conference on Composite Materials ICCM-9, July 12-16, Madrid, Spain.

10.

10. Boller, K. H. 1964. "Fatigue Characteristics of RP Laminates Subjected to Axial Loading," Modern Plastics, 41:145-145.

11.

11. Hahn, H. T. and R. Y. Kim . 1976. "Fatigue Behavior of Composite Laminate," J. Composite Materials, 10:156-180.

12.

12. Agarwal, B. D. and L. J. Broutman . 1980. Analysis and Performance of Fiber Composites. John Wiley & Sons.

13.

13. Ye, L. 1989. "On Fatigue Damage Accumulation and Material Degradation in Composite Materials," Composites Science and Technology, 36:339-350.

14.

14. Rotem, A. and H. G. Nelson . 1981. "Fatigue Behavior of Graphite-Epoxy Laminates at Elevated Temperatures," Fatigue of Fibrous Composite Materials, ASTM STP 723, p. 152-173.

15.

15. Hashin, Z. and A. Rotem . 1973. 'A Fatigue Failure Criterion for Fiber Reinforced Materials," J.Composite Materials, 7:448-464.

16.

16. Reifsnider, K. L. and Z. Gao . 1991. 'A Micromechanics Model for Composites under Fatigue Loading," Int. J. Fatigue, 13:149-156.

17.

17. Zhurkov, S. N. 1968. "Kinetic Concept of Strength of Solid Bodies," Vestnik AN SSSR pp. 46-52 (in Russian).

18.

18. Zhurkov, S. N. 1984. "Kinetic Concept of the Strength of Solids," Int. J. Fracture. 26:295-307.

19.

19. Dzenis, Y. A. , A. E. Bogdanovich and C. M. Pastore . 1992. "Stochastic Damage Evolution in Textile Laminates," Proceedings of the Sixth Conference on Advanced Engineering Fibers and Textile Structures for Composites FIBER-TEX92, Philadelphia, PA, pp. 235-248.

20.

20. Dzenis, Y. A. and S. P. Joshi . 1993. "Damage Induced Anisotropy in Laminates," Advanced Composites Letters, 2:97-99.

21.

21. Dzenis, Y. A. and S. P. Joshi . "Effect of Loading Parameters on Damage Induced Shear Extension Coupling in Laminates," Advanced Composites Letters (to be submitted).

22.

22. Dzenis, Y. A. and S. P. Joshi . 1994. "Inhomogeneous Anisotropic Percolation: 2D Numerical Threshold Analysis," Physical Review B, 49:3566-3568.

Stochastic Damage Evolution Modeling in Laminates

Abstract

References