We investigate two classes of materials whose properties emerge from a carefully crafted microstructure: origami tessellations and knitted fabric. These materials exhibit exotic mechanical properties, such as negative Poisson’s ratio, or extreme stretchability.
After characterizing the constitutive behavior of a single crease, we study origami mechanics in the limits of rigid faces and rigid creases, which both display some form of metastability in generic situations. In a second part, we focus on the mechanical response of knitted fabrics. We derive the response of these materials from first principles and successfully compare to experimental results. Surprisingly however, we uncover crackling noise in their quasi-static response and heterogeneous rearrangements within the fabric. A statistical analysis of these phenomena points to a deep similarity with earthquakes in geological faults.
A coffee break will be served at 11h00.
CNRS, Laboratoire de Physique Statistique, Ecole Normale Supérieure, Paris