Maio 2014 vol. 1 num. 1 - 10th World Congress on Computational Mechanics
Full Article - Open Access.
FINITE ELEMENT APPLICATION TO DUCTILE FRACTURE PROBLEMS INVOLVING HIGH NUMBER OF DEGREES OF FREEDOM
The aim of this paper is to show, using an example, the finite element potential to simulate ductile fracture problems involving high number of degrees of freedom. The example consists of a model proposed by Gologanu, Leblond, Perrin and Devaux (GLPD model) to describe ductile fracture. This model is an extension of the famous Gurson’s model to address the underlying unlimited localization problem arising in the Gurson model. The GLPD model was derived from some refinement of Gurson’s original homogenization procedure; the new model is of “micromorphic” nature, involving the second gradient of the macroscopic velocity and generalized macroscopic stresses of “moment” type, together with some characteristic “microstructural distance”. The numerical implementation of this model into finite element codes is quite involved, since its requires the use of finite element of class C1 and the solution of a complex “projection onto the yield locus” problem. Enakoutsa and Leblond have proposed a numerical scheme that avoids these two difficulties. We present here some new assessments of this numerical scheme. First, we develop an analytical solution for the problem of an elastic hollow sphere, obeying the GLPD model and subjected to hydrostatic tension; this solution agrees very well with the numerical predictions of the GLPD model. Also, comparisons between experimental and numerical load vs. displacement curves for an axisymmetric pre-cracked spcimen made of typical stainless steel are found to yield satisfatory results.
Palavras-chave: Ductile Fracture, Micromorphic, Numerical implementation,
-  Enakoutsa K., Leblond J.B. and Perrin G., 2007. “Numerical Implementation and Assessment of a Phenomenological NonlocalModel of Ductile Rupture,” Comput. Meth. Appl. Mech. Engng., 196, 1946-1957.
-  Enakoutsa K. and Leblond J.B., 2009. “Numerical Implementation and Assessment of a Phenomenological Nonlocal Model of Ductile Rupture,” Comput. Meth. Appl. Mech. Engng., 196, 1946-1957.
-  Gologanu M., Leblond J.B., Perrin G. and Devaux J., 1997. Recent extensions of Gurson’s model for porous ductile metals, in: Continuum Micromechanics, CISM Courses and Lectures 377, P. Suquet ed., Springer, pp. 61-130.
-  Gurson A.L. 1977. “Continuum Theory of Ductile Rupture by Void Nucleation and Growth: Part I - Yield Criteria and Flow Rules for Porous Ductile Media,” ASME J. Engng. Materials Technol., 99, 2-15.
-  Pijaudier-Cabot, G. and Bazant, Z.P., 1987.“Nonlocal Damage Theory”, ASCE J. Engnrg. Mech., 113, 1512-1533.
-  Tvergaard, V., 1981. “Influence of voids on shear band instabilities under plane strain conditions,” Int. J. Fracture, 17, 389-407.
-  Tvergaard, V. and Needleman, A., 1984. “Analysis of cup-cone fracture in a round tensile bar,” Acta Metallurgica, 32, 157-169.
-  Rousselier, G. and Mudry, F., 1983. “Etude de la rupture ductile de l’acier faiblement allie en Mn-Ni-Mo pour cuves de reacteurs a eau ordinaire sous pression, approvisionne sous la forme d’une debouchure de tubulure. Resultats du programme experimental,” EdF Centre des Renardieres Internal Report HT/PV D529 MAT/T43 (in French).
Enakoutsa, Koffi; "FINITE ELEMENT APPLICATION TO DUCTILE FRACTURE PROBLEMS INVOLVING HIGH NUMBER OF DEGREES OF FREEDOM", p. 3485-3496 . In: In Proceedings of the 10th World Congress on Computational Mechanics [= Blucher Mechanical Engineering Proceedings, v. 1, n. 1].
São Paulo: Blucher,
ISSN 2358-0828, DOI 10.5151/meceng-wccm2012-19379
últimos 30 dias | último ano | desde a publicação