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Anisotropic constitutive equations and experimental tensile behavior of brain tissue.

Section of Pediatric Neurosurgery, Institute of Neurosurgery, Catholic University Medical Centre, Largo A. Gemelli 1, 00168 Rome, Italy.
Biomechanics and Modeling in Mechanobiology (Impact Factor: 3.33). 04/2006; 5(1):53-61. DOI: 10.1007/s10237-005-0007-9
Source: PubMed

ABSTRACT The present study deals with the experimental analysis and mechanical modeling of tensile behavior of brain soft tissue. A transversely isotropic hyperelastic model recently proposed by Meaney (2003) is adopted and mathematically studied under uniaxial loading conditions. Material parameter estimates are obtained through tensile tests on porcine brain materials accounting for regional and directional differences. Attention is focused on the short-term response. An extrapolation of tensile test data to the compression range is performed theoretically, to study the effect of the heterogeneity in the tensile/compressive response on the material parameters. Experimental and numerical results highlight the sensitivity of the adopted model to the test direction.

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