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TRANSIENT ANALYSIS OF GEOMETRICALLY NON-LINEAR TRUSSES CONSIDERING COUPLED PLASTICITY AND DAMAGE

Suzuki, J. L.; Muñoz-Rojas, P. A.;

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The fracture of ductile materials is usually preceded by considerable levels of plastic strain. After a first stage in which plastic strain strengthens the material due to the introduction and increase of dislocations (hardening), a degradation phenomenon begins to take place due to the nucleation of microcracks and microvoids. The nucleation, growth and coalescence of these defects can be modeled using the concepts of Continuum Damage Mechanics. In this theory, a continuous damage variable is defined, which evolves coupled to plastic strain until attaining a critical value associated to rupture. Several damage models have been proposed for ductile materials, two of the most important being attributed to Gurson and to Lemaitre. This work evaluates the effect of Lemaitre’s damage model when applied to 3D trusses subjected to geometrical nonlinearities including inertial forces. To this end, two different damage evolution laws found in the literature are studied and compared. Special attention is given to unstable problems such as snap-through, in which results show that the effect of inertial forces is predominant. Furthermore, it becomes evident that for a realistic description of damage evolution and failure prediction, a different treatment must be given to tensile and compressive states. The work is closed by the discussion of damping effects on the damaged dynamic problem. It should be remarked that the evaluation of coupled plasticity and damage including geometrical nonlinearities, inertial forces and damping is a complex problem. Hence, setting these phenomena in a simple 3D truss framework makes it possible to focus on the description of physical behavior rather than on element technology complexities. This allows a clear understanding of some effects of Lemaitre’s damage, paving the way for implementations using 2D and 3D continuum finite elements.

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Palavras-chave: Finite element method, Continuum damage mechanics, Geometric nonlinearity,

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DOI: 10.5151/meceng-wccm2012-16750

Referências bibliográficas
  • [1] F.X.C Andrade and P.A. Muñoz Rojas. Geometric Nonlinear Analysis of 3D Elasto- Viscoplastic Trusses. CILAMCE, Espírito Santo, 2005.
  • [2] R. R. Auerswaldt. Dynamic Analysis of nonlinear viscoelastic cables and trusses undergoing finite displacements. Internal Report, Laboratório de Mecãnica Computacional, Departamento de Engenharia Mecânica, UDESC, Joinville, Brazil, 2009.
  • [3] M.A Dokainish and K. Subbaraj. A Survey of Direct Time-Integration Methods in Computacional Structural Dynamics .1. Explicit Methods, volume 32. Computers and Structures, 1989.
  • [4] M.A Dokainish and K. Subbaraj. A Survey of Direct Time-Integration Methods in Computacional Structural Dynamics .2. Implicit Methods, volume 32. Computers and Structures, 1989.
  • [5] L. Driemeier, S.P.B. Proença, and M. Alves. A contribution to the numerical analysis of three-dimensional truss systems considering large strains, damage and plasticity. Science Direct, 2004.
  • [6] Andresa Freitas. Modelagem da evolução do dano ortotrópico acoplado à elastoplasticidade em metais. Universidade Federal de Santa Catarina, 2010.
  • [7] L.M. Kachanov. Time rupture process under creep conditions. Izv Akad Nauk SSR, 1958.
  • [8] J. Lemaitre. A Course on Damage Mechanics. Springer, second edition, 1996.
  • [9] Jean Lemaitre. A continuous damage mechanics model for ductile fracture. Journal of engineering and materials technology, 1985.
  • [10] P.A. Muñoz Rojas and L.A. Duarte Filho. Análise Não-Linear Geométrica e Material de Treliças Espaciais, CE-60. UFRGS, 2001.
  • [11] Y.N. Rabotnov. Creep problems in structural members. North-Holland, 1969.
  • [12] S. Semptikovski and P.A. Muñoz Rojas. Modeling a Gemetrically Nonlinear Beam Element with Simplified Bending Stiffness and Linear Viscoelastic Behavior. XXXII Iberian Latin-American Congress on Computational Methods in Engineering, Ouro Preto, 2011.
  • [13] J.C. Simo and T.J.R. Hughes. Computational Inelasticity. Springer-Verlag, 1998.
  • [14] M. Vaz, P.A. Muñoz Rojas, and M.R. Lange. Damage evolution and thermal coupled effects in inelastic solids, volume 53. International Journal of Mechanical Sciences, 2011.
Como citar:

Suzuki, J. L.; Muñoz-Rojas, P. A.; "TRANSIENT ANALYSIS OF GEOMETRICALLY NON-LINEAR TRUSSES CONSIDERING COUPLED PLASTICITY AND DAMAGE", p. 322-341 . In: In Proceedings of the 10th World Congress on Computational Mechanics [= Blucher Mechanical Engineering Proceedings, v. 1, n. 1]. São Paulo: Blucher, 2014.
ISSN 2358-0828, DOI 10.5151/meceng-wccm2012-16750

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