Summary
It has been established that the elliptic paraboloid failure criterion (EPFC) is a potential means of describing the yielding and failure behavior of transversely isotropic (transtropic) materials presenting also strength differential effects along all principal stress axes. The cases studied correspond to symmetric forms of loading which are parallel to the principal strength directions of the material.
In this paper the general case of an orthotropic material not presenting any kind of strength symmetry was encountered. It has been shown that an elloptic parabloid surface may continue to represent the failure surface of such materials. However the symmetry of this surface relatively to the principal diagonal plane containing the strong σ3-axis and the bisector of the two remaining axes is destroyed. For these materials the elliptic paraboloid is leaning toward the intermediate strength σ2-axis and the angle of inclination of the plane of symmetry of the paraboloid with the σ1σ2-plane depends on the difference in strengths between the σ2- and σ1-axes. The characteristic properties of the inclined paraboloid were studied and important differences between the inclined and the symmetric surfaces were established. Examples with orthotropic polymers and composites were included exemplifying the characteristic properties of orthotropic materials.
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References
Hill, R.: A theory of the yielding and plastic flow of anisotropic metals. Proc. Roy. Soc. Lond., Ser. A193, 281–297 (1948).
Von Mises, R.: Mechanik der plastischen Formänderung von Kristallen. Zeit. ang. Math. und Mech.8, 161–185 (1928).
Hoffman, O.: The brittle strength of orthotropic materials. Jnl. Comp. Mat.1, 200–206 (1967).
Coulomb, C. A.: Essai sur l'application des règles des maximis et minimis à quelques problèmes de statique relatifs à l'architecture. Mémoires de Mathématiques et de Physique, Acad. Roy. des Sciences par divers savants,7, 343–382 (1773).
Tsai, S. W., Wu, E. M.: A general theory of strength for anisotropic materials. Jnl. Comp. Mat.5, 58–80 (1971).
Theocaris, P. S.: Yield criteria based on void coalescence mechanisms. Intern. Jnl. Solids and Struct.22 (4), 445–466 (1986).
Theocaris, P. S.: Generalized failure criteria in the principal stress space. Theoret. and Appl. Mech., Bulgarian Academy of Sciences19 (2), 74–104 (1987).
Theocaris, P. S.: Failure and fracture criteria in composites. Proc. Intern. Conf. of Measure. of Static and Dyn. Parameters of Structures and Materials, Plzen Czech., IMECO TC15 Publ.2, 547–557 (1987).
Theocaris, P. S.: Failure criteria for engineering materials based on anisotropic hardening. Proc. Nat. Acad. Athens61 (I), 84–114 (1986).
Tschoegl, N. W.: Failure surfaces in principal stress space, molecular order-molecular motion: their response to macroscopic stresses. Jnl. Polymer Sci., Part C, Polymer Symposia32 (Kausch, H. H., ed.) pp. 239–267, New York: Interscience 1971.
Theocaris, P. S., Philippidis, Th.: The paraboloidal failure surface of initially anisotropic elastic solids. Jnl. of Reinf. Plastics and Comp.6 (4), 378–395 (1987).
Theocaris, P. S.: The elliptic paraboloid failure surface for 2D-transtropic plates (Fiber laminates). Engng. Fract. Mech.33, in print (1989).
Theocaris, P. S.: Failure criteria for transtropic pressure dependent materials: the fiber composites. Rheologica Acta27 (5), 451–465 (1988).
Theocaris, P. S.: Failure characterization of anisotropic materials by means of the elliptic paraboloid failure criterion. Uspechi Mechanikii (Advances of Mechanics)10 (3), 75–129 (1987).
Theocaris, P. S.: Orthogonal components of elastic energy in transtropic materials by the use of the elliptic paraboloid failure surface. Acta Mechanica77, 69–89 (1989).
Theocaris, P. S.: Decomposition of strain energy density in fiber reinforced composites. Engng. Fract. Mech.33, in print (1989).
Theocaris, P. S.: The decomposition of the strain energy density in a fiber laminate to orthogonal components. Jnl. Reinf. Plast. Comp.8, in print (1989).
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Theocaris, P.S. The paraboloid failure surface for the general orthotropic material. Acta Mechanica 79, 53–79 (1989). https://doi.org/10.1007/BF01181480
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DOI: https://doi.org/10.1007/BF01181480