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A variational constitutive model for soft biological tissues

El Sayed, Tamer and Mota, Alejandro and Fraternali, Fernando and Ortiz, Michael (2008) A variational constitutive model for soft biological tissues. Journal of Biomechanics, 41 (7). pp. 1458-1466. ISSN 0021-9290.

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In this paper, a fully variational constitutive model of soft biological tissues is formulated in the finite strain regime. The model includes Ogden-type hyperelasticity, finite viscosity, deviatoric and volumetric plasticity, rate and microinertia effects. Variational updates are obtained via time discretization and pre-minimization of a suitable objective function with respect to internal variables. Genetic algorithms are used for model parameter identification due to their suitability for non-convex, high dimensional optimization problems. The material behavior predicted by the model is compared to available tests on swine and human brain tissue. The ability of the model to predict a wide range of experimentally observed behavior, including hysteresis, cyclic softening, rate effects, and plastic deformation is demonstrated.

Item Type:Article
Related URLs:
URLURL TypeDescription
Fraternali, Fernando0000-0002-7549-6405
Ortiz, Michael0000-0001-5877-4824
Additional Information:© 2008 Elsevier. Accepted 18 February 2008, Available online 17 April 2008. The authors would like to thank Professor Francesschini and Professor Bigoni for their indispensable collaboration. Also, F.F. greatly acknowledges the support of the Italian Fulbright Commission and the Council for International Exchange of Scholars. There are no conflicts of interest of any kind in the work presented in the manuscript.
Funding AgencyGrant Number
Italian Fulbright CommissionUNSPECIFIED
Council for International Exchange of ScholarsUNSPECIFIED
Subject Keywords:Biological tissues; Variational; Ogden; Plasticity; Shear; Volumetric damage; Finite strain; Cavitation; Genetic algorithms; Hyper elasticity; Viscosity; Microinertia
Issue or Number:7
Record Number:CaltechAUTHORS:20180112-160452524
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Official Citation:Tamer El Sayed, Alejandro Mota, Fernando Fraternali, Michael Ortiz, A variational constitutive model for soft biological tissues, Journal of Biomechanics, Volume 41, Issue 7, 2008, Pages 1458-1466, ISSN 0021-9290, (
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:84321
Deposited By: Lydia Suarez
Deposited On:17 Jan 2018 18:22
Last Modified:24 Feb 2020 10:30

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