Computational Mechanics

, Volume 12, Issue 5, pp 277–296 | Cite as

An analysis of strong discontinuities induced by strain-softening in rate-independent inelastic solids

  • J. C. Simo
  • J. Oliver
  • F. Armero

Abstract

Ket qualitative features of solutions exhibiting strong discontinuities in rate-independent inelastic solids are identified and exploited in the design of a new class of finite element approximations. The analysis shows that the softening law must be re-interpreted in a distributional sense for the continuum solutions to make mathematical sense and provides a precise physical interpretation to the softening modulus. These results are verified by numerical simulations employing a regularized discontinuous finite element method which circumvent the strong mesh-dependence exhibited by conventional methods, without resorting to viscosity or introducing additional ad-hoc parameters. The analysis is extended to a new class of anisotropic rate-independent damage models for brittle materials.

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Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • J. C. Simo
    • 1
    • 2
  • J. Oliver
    • 1
    • 2
  • F. Armero
    • 1
    • 2
  1. 1.Division of Applied MechanicsStanford UniversityUSA
  2. 2.ETS Ing. CCPUniversitat Politecnica de CatalunyaBarcelonaSpain

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