Large strain behaviour of brain tissue in shear: some experimental data and differential constitutive model

Biorheology. 2001;38(4):335-45.

Abstract

In this paper, some experimental measurements of the behaviour of bovine brain tissue under large shear strains in vitro are reported, and a constitutive model which is consistent with the data is developed. It was determined that brain tissue is not strain-time separable, showing slower relaxation at higher strains, and that the stresses in shear are not linear with increasing shear strain. The new constitutive model is a differential model, including both an "elastic" term, of the Mooney type and a nonlinear viscoelastic term. The latter allows for the change in relaxation behaviour with strain, by modifying an upper convected multimode Maxwell model with a damping function. The model shows good agreement with the experimental shear results and could be used to describe other types of data.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / physiopathology*
  • Cattle
  • Computational Biology
  • Elasticity
  • In Vitro Techniques
  • Models, Biological
  • Rheology
  • Stress, Mechanical
  • Viscosity