Biomechanical Response of the Bovine Pia-Arachnoid Complex to Normal Traction Loading at Varying Strain Rates 2007-22-0004
The pia-arachnoid complex (PAC) covering the brain plays an
important role in the mechanical response of the brain due to
impact or inertial loading. The mechanical properties of the bovine
PAC under tensile loading have been characterized previously.
However, the transverse properties of this structure, such as shear
and normal traction which are equally important to understanding
the skull/brain interaction under traumatic loading, have not been
investigated. These material properties are essential information
needed to adequately define the material model of the PAC in a
finite element (FE) model of human brain.
The purpose of this study was to determine, experimentally, the
material properties of the PAC under normal traction loading. PAC
specimens were obtained from freshly slaughtered bovine subjects
from various locations. Quasi-static and dynamic tests along the
radial direction were performed at four different strain rates
(0.36, 2.0, 20.5, and 116.3 s-¹) to investigate the rate and
regional effects. Results suggest that the PAC under traction
loading is stiffer than brain tissue, rate dependent, and can be
characterized as linearly elastic until failure. However, no
regional difference was observed.