Unjamming as structural instability (honours thesis and presentation)
Abstract: The transition from solid-like to liquid-like behaviour of granular materials is investigated through analysis of mechanical stability beyond the scale of the individual contact: i.e on the scale of clusters of particles in the mesoscopic domain. This solid-liqiud like phase transition, otherwise known as “unjamming” in the physics community or “failure” in the engineering community, nucleates from inside the material. Mesoscopic structures emerge inside the material during deformation: like any structure, these are subject to instabilities that ultimately lead to failure. The failure of such structures on the mesoscale serves as “trigger events” or precursors to unjamming of the granular material on the macroscopic scale.
Abstract (from presentation): Granular materials are known to exhibit multiple personalities. In this presentation, the transition from solid-like to liquid-like behaviour of granular materials is investigated through analysis of mechanical stability on the scale of clusters of particles in the mesoscopic domain. Mesoscopic structures emerge inside the material during deformation: like any structure, these are subject to instabilities that ultimately lead to failure. The failures of such structures on the mesoscale serve as precursors to unjamming of the granular material on the macroscopic scale.