Ultrasonic guided waves in cortical bone modeled as a functionally graded anisotropic tube

Cécile Baron

The human cortical bone is a heterogeneous medium: it is multiscale and multicomponent. It can be seen as a bi-phasic material, pores full of marrow in a bone matrix, with an increasing porosity from the periosteum to the endosteum. This gradient of porosity reveals itself to be representative of the loss of mass, the changes of geometry (thinning) and the variation of structure (porosity) which occur with aging and are the determinants of the bone strength. After a process of homogenization, the cortical bone is considered as an anisotropic functionally graded waveguide. An original method is proposed to study the ultrasonic guided wave propagation in such a structure. Based on an analytical solution, the matricant, explicitly expressed under the Peano series expansion form, this approach allows to deal with a cylindrical geometry and a crystallographic symmetry less than the transversely isotropy. Moreover, a fluid-loading of the waveguide may be taken into account to better mimic the in-vivo conditions.

Mots clés: functionally graded material; ultrasonic guided waves; cortical bone

Domaines: Acoustique [physics.class-ph]

Cécile Baron. Ultrasonic guided waves in cortical bone modeled as a functionally graded anisotropic tube. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00810617⟩