Multiscale structure-functional modeling of lamellar bone

Abstract

Bone is a natural example of a structure that has achieved a unique combination and range of stiffness and strength. One of the striking features bone tissue is the ability to adapt to variable loading conditions by multiple but well organized structural arrangements of mineralized collagen fibrils at several levels of hierarchical organization. A profound understanding of the structure-function relations in bone requires both experimental assessment of heterogeneous elastic and structural parameters and theoretical modeling of the elastic deformation behavior. A "bottom-up" approach for experimental assessment and numerical modeling of the hierarchical structure from the nanoscale to the macroscale will be presented. Experimental data are obtained by scanning acoustic microscopy between 50 MHz and 1.2 GHz and provide anisotropic elastic and structural information at the lamellar (nanoscale) and at the tissue matrix (microscale) level. These data are directly translated into a Finite Element (FE) mesh. By numerical deformation analyses the homogenized elastic stiffness tensor of the next hierarchical levels (microscale to macroscale) are derived. At each level the numerical results are cross-validated by experimental data.