Computation for Rheological Phenomena of Elastic-Viscoplastic Body

Abstract

A computational method is proposed for simulating rheological phenomena of a body composed of a material such as soft soil, powder, and granular material under large excitations. These phenomena are considered to be elastic-viscoplastic (E-VP) flows with moving boundaries. Fundamental equations for the dynamics are constructed from the Eulerian viewpoint. The constitutive laws for pressure volume and deviatoric stress strain are E-VP and are expressed by differential equations. The pressure and deviatoric stress are combined to satisfy yield conditions. The equations construct the first-order partial differential equation system. A domain containing an E-VP body is divided into cells by applying a finite difference method to the partial differential equation system. The locations of markers distributed in the body are calculated to trace the moving free boundaries. The collapse of an E-VP square body is shown as an application example.