Nonlinear anisotropic composite biomechanical modeling of human skin

Abstract

A 3D nonlinear anisotropic composite biomechanical modeling of human skin was developed according to existing biomechanical experimental results, which can provide insights into the important structure-function relationship and parameters in skin tissue. A structural approach determines the macroscopic mechanical response of the skin tissue from its underlying structural components. The collagen fibers were embedded into a block of elastic gel matrix. The constitutive matrix of skin tissue consisted of both of collagen fiber and elastic gel block according to the rule that the collagen fibers were undulated with the ability to resist load only when completely straightened. The nonlinear and anisotropic mechanical responses were largely due to varying degree of fiber undulation. Statistical distributions were used to determine the extent of fiber undulation. The comparison of stress-strain plots between the modeling and experimental results showed the good coordination of the both. Some model parameters were discussed to compute the macroscopic mechanical response when the tissue block was subject to a simple deformation mode.