Analytical model of the longitudinal break of a unidirectional composite with natural fibers

Analytical model of the longitudinal break of a unidirectional composite with natural fibers

Bachir BouhamidaZouaoui Sereir Alaa Chateauneuf 

Laboratoire Structures de Composites et Matériaux Innovants Faculté de génie mécanique, Université des Sciences et Technologie Mohamed Boudiaf BP 1505 El M’Naouer, Oran, Algérie

LaMI, Université Blaise Pascal, EA 3867 BP 10448, 63000 Clermont-Ferrand, France

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The present work aims at developing an analytical model of shear-lag of a cell of unidirectional composites made from natural fibers (Alfa) with irregular spacing between fibers. The finite difference method is used to calculate the "Stress Concentration Factor" (SCF) at the neighboring fibers. By the development of a pattern of three-dimensional finite differences with random spacing between fibers, a coupled system of equations is obtained for the displacement and stress concentration in the fibers. By varying the distance between the fibers and their diameters, the sensitivity distribution of the SCF is evaluated along the fibers. A probabilistic analysis of a cell of a unidirectional composite having a break in the central fiber is then conducted to evaluate the effect of geometrical and mechanical uncertainties on the evolution of the stress concentration. The probabilistic study is performed using Monte Carlo simulations to assess the sensitivity of the model with respect to geometrical and mechanical uncertainties.


unidirectional composite, natural fiber, broken fiber transfer, finite difference, stress concentration.

Extended abstract
1. Introduction
2. Extraction de la fibre Alfa
3. Caractérisation de la fibre alfa
4. Modèle numérique développé
5. Résultats de l’approche fiabiliste du modèle mécanique
6. Conclusion

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