Bounds on size-dependent behavior of composites
Saeb S, Steinmann P, Javili A (2017)
Publication Type: Journal article
Publication year: 2017
Journal
Book Volume: 17
Pages Range: 1-27
DOI: 10.1080/14786435.2017.1408967
Abstract
Computational homogenisation is a powerful strategy to predict the effective behaviour of heterogeneous materials. While computational homogenisation cannot exactly compute the effective parameters, it can provide bounds on the overall material response. Thus, central to computational homogenisation is the existence of bounds. Classical first-order computational homogenisation cannot capture size effects. Recently, it has been shown that size effects can be retrieved via accounting for elastic coherent interfaces in the microstructure. The primary objective of this contribution is to present a systematic study to attain computational bounds on the size-dependent response of composites. We show rigorously that interface-enhanced computational homogenisation introduces two relative length scales into the problem and investigate the interplay between them. To enforce the equivalence of the virtual power between the scales, a generalised version of the Hill--Mandel condition is employed, and accordingly, suitable boundary conditions are derived. Macroscopic quantities are related to their microscopic counterparts via extended average theorems. Periodic boundary conditions provide an effective behaviour bounded by traction and displacement boundary conditions. Apart from the bounds due to boundary conditions for a given size, the size-dependent response of a composite is bounded, too. The lower bound coincides with that of a composite with no interface. Surprisingly, there also exists an upper bound on the size-dependent response beyond which the expected `smaller is stronger' trend is no longer observed. Finally, we show an excellent agreement between our numerical results and the corresponding analytical solution for linear isotropic materials which highlights the accuracy and broad applicability of the presented scheme.
Authors with CRIS profile
Saba Saeb
Lehrstuhl für Technische Mechanik (LTM)
Paul Steinmann
Lehrstuhl für Technische Mechanik (LTM)
Additional Organisation(s)
Involved external institutions
Turkey (TR)How to cite
APA:
Saeb, S., Steinmann, P., & Javili, A. (2017). Bounds on size-dependent behavior of composites. Philosophical Magazine, 17, 1-27. https://doi.org/10.1080/14786435.2017.1408967
MLA:
Saeb, Saba, Paul Steinmann, and A. Javili. "Bounds on size-dependent behavior of composites." Philosophical Magazine 17 (2017): 1-27.
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