This course provided an overview of modeling approaches used in the
mechanics of inelastic materials and structures, with special attention
to the objective description of highly localized deformation modes such
as cracks or shear bands. It was organized as one of the
RILEM
educational courses.
In 2024 it attracted 20 participants arriving from Czechia, Germany, France, Poland, Austria, Brasil, Colombia and Sweden. This course will be given again in September 2025.
Independently of the course on Modeling of Localized Inelastic Deformation (LID2024), it was also possible to attend a course on OOFEM,
which took place at the same location on 9-11 September 2024.
OOFEM is an object-oriented open-source software package for solid mechanics,
with extensions to
fluid mechanics and transport problems.
Main topics
Introduction: notation, fundamentals of
tensor
algebra, strain localization and size effect, basic types of material models, techniques of
incremental-iterative nonlinear analysis.
Elastoplasticity:
physical motivation, basic equations in one dimension, extension to
multiaxial stress, associated
and nonassociated plastic flow, hardening and softening, tangent
stiffness.
Damage
mechanics: physical motivation, basic equations in one
dimension, isotropic damage models, smeared crack models, brief comments on anisotropic
damage models, damage
deactivation due to crack closure, combination of damage and plasticity.
Strain
localization: examples of localized failure,
onset of localization - incipient weak discontinuity,
localization analysis based on acoustic tensor, loss of ellipticity and
its mathematical and numerical consequences, classification of models
for localized inelastic behavior, mesh-adjusted softening modulus
(crack band approach).
Regularized
continuum
models: classification of enriched continuum
theories, nonlocal formulations of the integral type, explicit and
implicit gradient damage and plasticity formulations, variational damage models
and phase-field approaches,
micromorphic damage models, localization analysis, numerical aspects, implementation,
application examples.