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Marek Klisinski

Bio: Marek Klisinski is an academic researcher from Chalmers University of Technology. The author has contributed to research in topics: Constitutive equation & Structural system. The author has an hindex of 10, co-authored 18 publications receiving 333 citations. Previous affiliations of Marek Klisinski include Polish Academy of Sciences & University of Colorado Boulder.

Papers
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Journal ArticleDOI
TL;DR: In this article, a technique for modeling localized deformations within a softening band is described, where softening is attributed to a displacement discontinuity within an element, and the displacement field rather than the strain field is additively decomposed into elastic and inelastic parts.
Abstract: A new technique for modeling localized deformations within a softening band is described, where softening is attributed to a displacement discontinuity within an element. Concepts such as fracture strain are not included in the formulation of the model, and consequently nonlocal parameters such as internal length measures are not needed. It is shown that the shape functions within the element provide the necessary information normally given with internal length. In this manner, objectivity with regard to element configuration seems to be automatically satisfied, which is demonstrated by numerical studies in which Rankine failure criterion is employed. It is also noted that the displacement field rather than the strain field is additively decomposed into elastic and inelastic parts. This additivity is valid independently of the magnitude of displacement continuity in the softening band, which implies that the technique can be extended in a straight‐forward fashion to finite displacements.

102 citations

Journal ArticleDOI
TL;DR: In this article, a general theory that describes the cyclic loading behavior of different materials is presented, based on the theory of fuzzy sets, which allows us to define many different models within the same mathematical framework.
Abstract: This paper presents a general theory that describes the cyclic loading behavior of different materials. It is mathematically based on the theory of fuzzy sets. From the constitutive modeling point of view it is closely related to many previous cyclic plasticity models. Instead of utilizing two or more yield or bounding surfaces one more general surface is introduced in the space spanned by the stress and a membership function. This concept allows us to define many different models within the same mathematical framework. Several possibilities of the theory are examined with the aid of one-dimensional examples. The paper considers constitutive models with and without memory, as well as models with fading memory, with isotropic and kinematic hardening, as well as without hardening. The fuzzy-sets formulation describes different phenomena during cyclic loading such as hysteresis loops, cyclic stabilization effects, smooth elastic-plastic transition, and so on, which are illustrated with pertinent examples.

50 citations

Journal ArticleDOI
TL;DR: In this article, a general constitutive model for concrete is discussed in which the total strain rate is decomposed into elastic, plastic and damage strain rates, and rate equations are formulated for all strain rate portions together with evolution rules for hardening and damage state variables.

35 citations

Journal ArticleDOI
TL;DR: In this paper, the structure of incremental equations in plasticity is discussed with respect to the choice of control variables representing stress, strain or mixed control, while (quite independently) the yield surface may be represented in either stress or mixed space.

34 citations

Journal ArticleDOI
TL;DR: In this article, a general constitutive model based on seven parameters along with the secant stiffness method and the Rosenbrock's minimization algorithm is introduced to cope with more realistic material behavior in the structural optimization process.
Abstract: TO cope with more realistic material behavior in the structural optimization process, this paper introduces a general constitutive model based on seven parameters along with the secant stiffness method and the Rosenbrock's minimization algorithm. In addition, the concepts of reserve and residual strengths are used to study the effect of optimization on system strength and redundancy. Furthermore, stress and displacement behavioral constraints are considered both separately and simultaneously to investigate their influence on the optimum solution for brittle and ductile truss systems.

25 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, a constitutive model based on an internal variable-formulation of plasticity theory for the non-linear analysis of concrete is presented, which uses a new yield criterion which matches experimental data quite well and it accounts for both elastic and plastic stiffness degradations effects.

3,080 citations

BookDOI
17 Aug 2012
TL;DR: De Borst et al. as mentioned in this paper present a condensed version of the original book with a focus on non-linear finite element technology, including nonlinear solution strategies, computational plasticity, damage mechanics, time-dependent effects, hyperelasticity and large-strain elasto-plasticity.
Abstract: Built upon the two original books by Mike Crisfield and their own lecture notes, renowned scientist Rene de Borst and his team offer a thoroughly updated yet condensed edition that retains and builds upon the excellent reputation and appeal amongst students and engineers alike for which Crisfield's first edition is acclaimed. Together with numerous additions and updates, the new authors have retained the core content of the original publication, while bringing an improved focus on new developments and ideas. This edition offers the latest insights in non-linear finite element technology, including non-linear solution strategies, computational plasticity, damage mechanics, time-dependent effects, hyperelasticity and large-strain elasto-plasticity. The authors' integrated and consistent style and unrivalled engineering approach assures this book's unique position within the computational mechanics literature.

2,568 citations

Journal ArticleDOI
TL;DR: The nonlocal continuum concept has emerged as an effective means for regularizing the boundary value problems with strain softening, capturing the size effects and avoiding spurious localization that gives rise to pathological mesh sensitivity in numerical computations as mentioned in this paper.
Abstract: Modeling of the evolution of distributed damage such as microcracking, void formation, and softening frictional slip necessitates strain-softening constitutive models. The nonlocal continuum concept has emerged as an effective means for regularizing the boundary value problems with strain softening, capturing the size effects and avoiding spurious localization that gives rise to pathological mesh sensitivity in numerical computations. A great variety of nonlocal models have appeared during the last two decades. This paper reviews the progress in the nonlocal models of integral type, and discusses their physical justifications, advantages, and numerical applications.

1,171 citations

Journal ArticleDOI
TL;DR: In this paper, a model which allows the introduction of displacements jumps to conventional finite elements is developed, where the path of the discontinuity is completely independent of the mesh structure.
Abstract: A model which allows the introduction of displacements jumps to conventional finite elements is developed. The path of the discontinuity is completely independent of the mesh structure. Unlike so-called ‘embedded discontinuity’ models, which are based on incompatible strain modes, there is no restriction on the type of underlying solid finite element that can be used and displacement jumps are continuous across element boundaries. Using finite element shape functions as partitions of unity, the displacement jump across a crack is represented by extra degrees of freedom at existing nodes. To model fracture in quasi-brittle heterogeneous materials, a cohesive crack model is used. Numerical simulations illustrate the ability of the method to objectively simulate fracture with unstructured meshes. Copyright © 2001 John Wiley & Sons, Ltd.

914 citations

Journal ArticleDOI
TL;DR: A possible approach to their classification is suggested, with special attention to the type of kinematic enhancement and of internal equilibrium condition, by analyzing the behavior of the simplest finite element – the constant-strain triangle.

438 citations