View in EDS

A note on the stability of pressure-sensitive non-associated plasticity.

Saved in:
Bibliographic Details
Title: A note on the stability of pressure-sensitive non-associated plasticity.
Authors: Hofer, Paul1 (AUTHOR) Paul.Hofer@uibk.ac.at, Neuner, Matthias1,2 (AUTHOR), Hofstetter, Günter1 (AUTHOR)
Source: Computers & Geotechnics. Oct2025, Vol. 186, pN.PAG-N.PAG. 1p.
Subjects: Consciousness raising, Analytical solutions, Geotechnical engineering, Research personnel, Authorship in literature
Abstract: Stability issues related to non-associated plastic flow still present an often overlooked cause for numerical difficulties in finite element simulations of cohesive-frictional materials. Despite their significance, only few examples with analytical solutions exist that clearly illustrate the nature of the problem. In this note, we extend the existing literature by deriving a novel closed-form analytical solution for the elastoplastic behavior of non-associated Drucker-Prager plasticity subjected to oedometric extension. Moreover, we demonstrate that structural softening can arise even though material softening is not encompassed by the perfectly plastic model. By means of stability analysis based on the acoustic tensor criterion, we show that structural softening is concomitant with the loss of ellipticity of the governing rate equilibrium equations. The obtained results are illustrated through a numerical experiment, which highlights the encountered numerical difficulties, including non-objectivity of the obtained results and snap-back behavior. By means of this strikingly simple example, we aim to raise awareness about the peculiarities of non-associated plasticity among researchers, students and practitioners of geotechnical engineering alike. [ABSTRACT FROM AUTHOR]
Copyright of Computers & Geotechnics is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:Stability issues related to non-associated plastic flow still present an often overlooked cause for numerical difficulties in finite element simulations of cohesive-frictional materials. Despite their significance, only few examples with analytical solutions exist that clearly illustrate the nature of the problem. In this note, we extend the existing literature by deriving a novel closed-form analytical solution for the elastoplastic behavior of non-associated Drucker-Prager plasticity subjected to oedometric extension. Moreover, we demonstrate that structural softening can arise even though material softening is not encompassed by the perfectly plastic model. By means of stability analysis based on the acoustic tensor criterion, we show that structural softening is concomitant with the loss of ellipticity of the governing rate equilibrium equations. The obtained results are illustrated through a numerical experiment, which highlights the encountered numerical difficulties, including non-objectivity of the obtained results and snap-back behavior. By means of this strikingly simple example, we aim to raise awareness about the peculiarities of non-associated plasticity among researchers, students and practitioners of geotechnical engineering alike. [ABSTRACT FROM AUTHOR]
ISSN:0266352X
DOI:10.1016/j.compgeo.2025.107363