2019-Sustainable Industrial Processing Summit
SIPS2019 Volume 7: Schrefler Intl. Symp. / Geomechanics and Applications for Sustainable Development
| Editors: | F. Kongoli, E. Aifantis, A. Chan, D. Gawin, N. Khalil, L. Laloui, M. Pastor, F. Pesavento, L. Sanavia |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2019 |
| Pages: | 190 pages |
| ISBN: | 978-1-989820-06-3 |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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In Favour of Complexity in Modelling
Bernhard Schrefler1;1INSTITUTE FOR ADVANCED STUDY –TUM,, Munich, Germany;
Type of Paper: Plenary
Id Paper: 377
Topic: 51
Abstract:
Natural phenomena have mostly multiphysics and multiscale character. The same is true for many manmade materials. Multiphysics and multiscale models, if based on sound physical principles and satisfying the numerical requirements such a consistency and stability, can give much more insight in the phenomena under investigation than simpler models and can even allow for discoveries. I shall address a few of these cases where complex models made the difference. The use of an appropriate u-p model allowed to find that cavitation is needed for the onset of localization in dilatant porous media [1]. It also allowed to identify internal length scales governing the phenomenon. A three-fluids model for concrete, which considers a chemo-thermo-hydro-mechanical analysis taking into account of dry air, capillary and adsorbed water and water vapour in the pores allowed for a unified treatment of concrete under very high temperatures with particular regard to thermal spalling, tunnel fires and reactor vessels, concrete at early ages and beyond, leaching, Alkali-Aggregate reactions, freezing and thawing [2,3]. A model for fracturing in saturated porous media based on Biot’s theory, standard Galerkin Finite Elements, cohesive fracture and remeshing enabled to discover at least for the mechanics community that fracturing in saturated porous media is not continuous but stepwise with ensuing pressure oscillations [4,5]. This has important implications both in hydraulic fracturing operations and in geophysics, among others to reproduce the en echelon structure observed in nature. In material mechanics a truly multiscale model allowed to predict correctly the residual strains after cool down of Nb3 Sn superconducting strands [6]. Finally a multiphase model based on an transport oncophysics framework enabled to identify for instance a way to obtain less dense tumors which are desirable for drug delivery [7]. Other examples will be shown in the presentation.
Keywords:
Computational Geomechanics;References:
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3. “Modeling evolution of frost damage in fully saturated porous materials” (with M. Koniorczyk and D. Gawin), Comput. Methods Appl. Mech. Engrg., 292 (2015), 38-61.
4. “Mesh adaptation and transfer schemes for discrete fracture propagation in porous materials” (with S. Secchi and L. Simoni), Int. J. Numer. Anal. Meth. Geomech., (2007), 31:331-345