Numerical Analysis of the Response of Biomimetic Cellular Materials Under Static and Dynamic Loadings

Abstract

Biological structures distinguish themselves in preserving material heterogeneity for better mechanical behavior in contrast to man-made structures where they are deliberately removed through design. In this book chapter, we explore the distinct advantages in mechanical behavior brought about by regular, irregular, and functionally graded heterogeneities inherent in these cellular materials under quasi-static and dynamic crushing as well as impact loading. In particular we investigate energy dissipation and deformation modes during such loadings. We also investigate the effect of increasing self-similar structural hierarchy and cell wall material plasticity on the mechanical properties and failure behavior of these structures. Specifically, we discuss how mechanical response can be tuned using structural variations alone in particular, the tuning of strength to stiffness envelopes. Therefore, we show that material hierarchy can potentially reverse the conventional practice of design of structures using a variety of materials rather than vice versa. We also show how variation of structure can fundamentally change the deformation and damage patterns of these structures under dynamic crushing and impact loading. Finally we discuss some recent advances in fabrication and characterization of novel ultralight structures which exploit these essential self-similar properties of biological structures to create materials with remarkable stress–strain behavior strikingly different from the very materials originally used to make them.