Micromechanical modelling of the arterial wall: influence of mechanical heterogeneities on the wall stress distribution and the peak wall stress

Mamadou Toungara (1) , Laurent Orgéas (1) , Christian Geindreau (1) , Lucie Bailly (2)

1 3SR - Laboratoire sols, solides, structures - risques [Grenoble]
2 IRPHE - Institut de Recherche sur les Phénomènes Hors Equilibre

Previous tensile tests have shown the high anisotropy and heterogeneity of the arterial wall mechanical properties as a function of age, pathology (e.g. abdominal aortic aneurysm, AAA) and location (Vande Geest et al. 2006). The issues of this anisotropic behaviour and the AAA geometrical shapes have been tackled in many numerical studies. However, the wall mechanical heterogeneity has been very sparsely considered (Tierney et al. 2012). This work aims to study the effects of such heterogeneity on the stress distribution and the peak wall stress during a static pressurisation. Thence, a micromechani- cal-based model was used for the wall, and finite element analyses (FEA) were carried out on idealised AAAs. Unlike many previous phenomenological models, the current constitutive model depends on five material parameters only, which also allow us to control the wall microarchitecture.

Mots clés: abdominal aortic aneurysm; wall stress; anisotropy; heterogeneous mechanical properties

Domaines: Biomécanique [physics.med-ph]; Biomécanique [physics.med-ph]

Mamadou Toungara, Laurent Orgéas, Christian Geindreau, Lucie Bailly. Micromechanical modelling of the arterial wall: influence of mechanical heterogeneities on the wall stress distribution and the peak wall stress. 38th Congress of the Societe de Biomecanique, 2013, Marseille, France. pp.22-24, ⟨10.1080/10255842.2013.815929⟩. ⟨hal-00925438⟩