Equivalent Continuum Modeling for Shock Wave Propagation in Jointed Media

Abstract

This study presents discrete and continuum simulations of shock wave propagating through jointed media. The simulations were performed using the Lagrangian hydrocode GEODYN-L with joints treated explicitly using an advanced contact algorithm. They studied both isotropic and anisotropic joint representations. For an isotropically jointed geologic medium, the results show that the properties of the joints can be combined with the properties of the intact rock to develop an equivalent continuum model suitable for analyzing wave propagation through the jointed medium. For an anisotropically jointed geologic medium, they found it difficult to develop an equivalent continuum (EC) model that matches the response derived from mesoscopic simulation. They also performed simulations of wave propagation through jointed media. Two appraoches are suggested for modeling the rock mass. In one approach, jointed are modeled explicitly in a Lagrangian framework with appropriate contact algorithms used to track motion along the interfaces. In the other approach, the effect of joints is taken into account using a constitutive model derived from mesoscopic simulations.