Triantafyllos
Stylianopoulos

Diploma in Chemical Engineering,
National Technical University of Athens, Greece, 2003

Ph.D. Candidate, Chemical Engineering, University of Minnesota

styliano@cems.umn.edu

Bio

Stylianopoulos's CV

Research

MULTISCALE MODELING OF COLLAGENOUS MATERIALS

 It is our hypothesis that the overall mechanical behavior of collagenous materials, namely connective tissues and tissue equivalents, derives from the mechanics of the individual fibers and their interaction in the collagen network. Collagenous materials must function on the centimeter scale, while the underlying collagen network is typically on the micrometer scale. Therefore there is an inherently scale separation between the functional level and the structural level, which necessitates the use of multiscale techniques for the study of the mechanical behavior of the material.

We have developed a multiscale methodology, based on volume averaging theory, to relate the microstructure to the macroscopic mechanical function of tissues . In the model, a three-dimensional Galerkin finite element method is employed for the macroscale (tissue level) problem while the collagen microstructure is modelled as a three-dimensional, fibrillar network (averaging volume). The methodology does not use a macroscopic constitutive equation to relate the strain to the stress. Instead, an averaging volume is constructed at each Gauss point and the Cauchy stress tensor is calculated as the volume average of the local forces developed on the averaging volume.