Multiscale Phenomena in the Solid-Liquid Transition State of a Granular Material: Analysis, Modeling and Experimentation

摘要

In this research program, consisting of combined experiments, material characterization, modeling and simulations on sheared systems, we have: (a) mapped out the failure mechanism for force chains, and related these failures to the macroscopic state of the system under monotonic biaxial loading, (b) extended these studies to cyclic shear loading, (c) quantified nonaffine deformation at both the mesoscopic and macroscopic length scales, (d) correlated the above mechanisms and related these mechanisms to dissipation, (e) integrated all of the above findings into a new constitutive theory that embodies elements of thermomechanics (thermodynamics as it applies to constitutive development), micromechanics (a bottom-up approach aimed at developing constitutive laws whose material parameters are expressed in terms of particle scale properties), and micropolar theory (a continuum theory in which each material point bears both translational and rotational degrees of freedom).