Issue 60

A. Deliou et alii, Frattura ed Integrità Strutturale, 60 (2022) 30-42; DOI: 10.3221/IGF-ESIS.60.03

C ONCLUSION

T

he examined composite material is unidirectional Kevlar / Epoxy reinforcement. It is composed, in our case, of four layers whose arrangement constitutes symmetrical laminates [  /-  ] S . Our study allowed us to observe an elastic phase of the material until rupture, with the absence of the plastic phase. In addition, we noticed the absence of coupling between the tensile membrane force and the angular distortion of the material due to the balanced arrangement of the laminates. The study of the deformations for different stacking sequences made us choose the cross laminate as the best configuration. Among variety of failure criteria, we have chosen that of Tsai-Hill for unidirectional composites, especially when the orientation of the layers is in the vicinity of 0° and smaller than 28°. In addition, results obtained with then different criteria, are similar when moving forward 90°. The maximum stress theory makes it possible to determine three modes of rupture of the outer plies which are resistant. The curves of the envelopes of failure obtained by the criterion of Tsai-Hill, present elliptical shapes; on the other hand the theory of the maximum stress theory allowed us to obtain rectangles which are independent of the influence of the tangential component of the tensor of the stresses applied to the external layer. [1] Brandt, J. Dreschler, K. and Arendts, F.J. (1996). Mechanical performance of composites based on various three- dimensional woven fibre performs. Composites Science and Technology, 56, pp. 381–386. DOI: 10.1016/0266-3538(95)00135-2. [2] Liu, K.S. and Tsai, S.W. (1998). A Progressive Quadratic Failure Criterion for a Laminate, Composites Science and Technology, 58(7), pp.1023–1032. DOI: 10.1016/S0266-3538(96)00141-8. [3] Hill, R. (1963). Elastic Properties of Reinforced Solids: Some Theoretical Principles. Journal of the Mechanics and Physics of Solids, 11, pp.357-372. DOI: 10.1016/0022-5096(63)90036-X. [4] Azzi, V.D. and Tsai S.W. (1965). Anisotropic Strength of components. Experimental Mechanics, 5, pp. 286-288. DOI: 10.1007/BF02326292 [5] Tsai, S. W. and Wu, E. M. (1971). A General Theory of Strength for Anisotropic Materials. Journal of Composite Materials, 5(1), pp. 58–80. DOI:10.1177/002199837100500106. [6] Berthelot, J. M. ed. (2012). Matériaux composites: Comportement mécanique et analyse des structures, Paris, Lavoisier. [7] Renard, J. ed. (2005). Elaboration, microstructure et comportement des matériaux composites à matrice polymère. Paris: Hermes science. [8] Puck, A. and Schürmann, H. (2002). Failure theories of FRP laminates by means of physically based phenomenological models. Composites Sci. Technol., 62(12-13), pp. 1633–1662. DOI: 10.1016/S0266-3538(01)00208-1. [9] Soden, P. (1998). Lamina properties, lay-up configurations and loading conditions for a range of fibre-reinforced composite laminates. Composites Science and Technology, 58(7), pp.1011–1022. DOI:10.1016/s0266-3538(98)00078-5. [10] Hinton, M., Kaddour, A. and Soden, P. (2002). A comparison of the predictive capabilities of current failure theories for composite laminates, judged against experimental evidence. Composites Science and Technology, 62(12-13), pp.1725–1797. DOI:10.1016/s0266-3538(02)00125-2. [11] Yeh, H.-L. (2003). Quadric Surfaces Criterion for Composite Materials. Journal of Reinforced Plastics and Composites, 22(6), pp. 517–532. DOI:10.1106/073168403023274. [12] Irhirane, E. H., Echaabi, J., Aboussaleh, M., Hattabi, M. and Trochu, F. (2008). Matrix and Fibre Stiffness Degradation of a Quasi-isotrope Graphite Epoxy Laminate Under Flexural Bending Test. Journal of Reinforced Plastics and Composites, 28(2), pp. 201–223. DOI:10.1177/0731684407084213. [13] Christensen, R. M. (1990). Tensor Transformations and Failure Criteria for the Analysis of Fiber Composite Materials Part II: Necessary and Sufficient Conditions for Laminate Failure. Journal of Composite Materials, 24(8), pp. 796– 800. DOI:10.1177/002199839002400801. R EFERENCES

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