The influence of the specimen shape and loading conditions on the parameter identification of a viscoelastic brain model
type: Item
instance of: scholarly article
title: The influence of the specimen shape and loading conditions on the parameter identification of a viscoelastic brain model
zbMATH Open document ID: 1307.92054
DOI: 10.1155/2013/460413
author: Costin D. Untaroiu
published in: Computational \& Mathematical Methods in Medicine
publication date: 2015-03-16T00:00:00Z
review text: Summary: The mechanical properties of brain under various loadings have been reported in the literature over the past 50 years. Step-and-hold tests have often been employed to characterize viscoelastic and nonlinear behavior of brain under high-rate shear deformation; however, the identification of brain material parameters is typically performed by neglecting the initial strain ramp and/or by assuming a uniform strain distribution in the brain samples. Using finite element (FE) simulations of shear tests, this study shows that these simplifications have a significant effect on the identified material properties in the case of cylindrical human brain specimens. Material models optimized using only the stress relaxation curve under predict the shear force during the strain ramp, mainly due to lower values of their instantaneous shear moduli. Similarly, material models optimized using an analytical approach, which assumes a uniform strain distribution, under predict peak shear forces in FE simulations. Reducing the specimen height showed to improve the model prediction, but no improvements were observed for cubic samples with heights similar to cylindrical samples. Models optimized using FE simulations show the closest response to the test data, so a FE-based optimization approach is recommended in future parameter identification studies of brain.
Mathematics Subject Classification ID: 92C30
Mathematics Subject Classification ID: 65L60
zbMATH DE Number: 6414975
Wikidata QID: Q39368789
MaRDI profile type: Publication
full work available at URL: https://doi.org/10.1155/2013/460413
OpenAlex ID: W2015674770
description: scientific article