Continuum description of the time- and strain-dependent Poisson's ratio of ligament under finite deformation

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Publication Type thesis
School or College College of Engineering
Department Biomedical Engineering
Author Swedberg, Aaron
Title Continuum description of the time- and strain-dependent Poisson's ratio of ligament under finite deformation
Date 2014-05
Description Ligaments and tendons undergo volume loss when stretched along the primary fiber axis, which is evident by the large, strain-dependent Poisson's ratios measured during quasistatic tensile tests. When continuum constitutive models have been used to describe ligament material behavior they have generally assumed incompressibility, which does not reflect the volume loss seen experimentally. We developed a strain energy equation that can predict both the nonlinear, transversely isotropic behavior as well as the large, strain-dependent Poisson's ratios seen experimentally. This hyperelastic constitutive model was implemented in the finite element solver FEBio and the quasistatic and time-dependent material behaviors were compared to a nearly incompressible constitutive model. The new model was able to predict uniaxial stress-strain behavior comparable to the nearly incompressible model and successfully predicted a large, strain-dependent Poisson's ratio. Biphasic simulations that represented the solid phase with the constitutive model predicted a large outward fluid flux and substantial stress-relaxation, suggesting that the viscoelastic behavior of ligaments and tendons can be predicted by modeling fluid movement when combined with a large Poisson's ratio.
Type Text
Publisher University of Utah
Subject Constitutive model; Finite element analysis; Ligament; Poisson's ratio; Tendon
Dissertation Institution University of Utah
Dissertation Name Master of Science
Language eng
Rights Management Copyright © Aaron Swedberg 2014
Format Medium application/pdf
Format Extent 756,378 Bytes
Identifier etd3/id/3503
ARK ark:/87278/s6xd48xz
Setname ir_etd
ID 197056
Reference URL https://collections.lib.utah.edu/ark:/87278/s6xd48xz