Strategies and challenges for the mechanical modeling of biological and bio-inspired materials

The mechanical modeling of biological materials has received much attention due to diverse applications in medicine and engineering. Biological materials are often structurally hierarchical and may possess highly desirable structure–property relations that serve as templates for bio-inspired materials. This paper reviews the strategies that have been employed for the mechanical modeling of biological and bio-inspired materials, and outline the outstanding challenges. The review focuses on models based on the following approaches: single-scale versus multi-scale, microstructural versus phenomenological, and continuum versus discrete. Challenges in scale-bridging, integrated microstructural representation at all hierarchies and accurate constitutive modeling are discussed. In particular, inverse modeling and cross-property correlations are viewed as future challenges for the modeling of bio-inspired materials.