2015-Sustainable Industrial Processing Summit
SIPS 2015 Volume 1: Aifantis Intl. Symp. / Multiscale Material Mechanics
| Editors: | Kongoli F, Bordas S, Estrin Y |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2015 |
| Pages: | 300 pages |
| ISBN: | 978-1-987820-24-9 |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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Deformation Version of Gradient Plasticity and Size Effects in Elastoplastic Axisymmetric Boreholes
George Efremidis1;1UNIVERSITY OF THESSALY, Volos, Greece;
Type of Paper: Regular
Id Paper: 275
Topic: 1
Abstract:
The use of a deformation version of gradient plasticity in order to obtain the analytical solution of the elastoplastic axisymmetric borehole, subjected to a far-field biaxial tension, has been provided. The constitutive model results from the basic assumption of a gradient depended flow stress, i.e. the dependence of the effective stress on the Laplacian of the effective strain. Deformation theory is formulated within an approximate strength of materials approach, utilizes an averaging process over the entire deformation history and relates the total plastic strain to the final total stress. The elastic part of the problem was considered through the classical elasticity theory. The analytical solution and the results, i.e. the distributions of stresses and strains, are illustrated and compared in the context of the size effects which contribute to the study of the borehole stability.
Keywords:
Elastoplastic boreholes; Deformation theory; Gradient plasticity; Size effectsReferences:
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