Cellular automaton modelling of heterogeneous rock failure processes

摘要

This paper summarizes the use of the cellular automaton model in the modeling of rock failure processes. Three cellular automaton models, i.e. the physical cellular automaton (PCA), lattice cellular automaton (LCA), and elasto-plastic cellular automaton (EPCA), developed by the authors are presented and the associated applications described. The paper concentrates on the theory, basic ideas and application of the elasto-plastic cellular automaton which is an integration of elasto-plastic theory, cellular automaton theory, statistical theory, and rock mechanics.. In this study, a series of numerical tests, including rock failure processes under uniaxial compression, failure processes of rocks under cyclic loading and the simulation of Class I and Class II complete stress-strain curves, were conducted to reproduce some of the typical experimental phenomena. It is found that the EPCA model has the ability to simulate the initiation, propagation and coalescence of micro-cracks of rocks during the failure processes. The EPCA was also used to study the evolution of stress and deformations, as well as failure and permeability evolution in the Excavation Disturbed Zone (EDZ) of crystalline rocks. The results highlight the strong impact of fractures, and plastic deformation on the behavior of the EDZ, especially the evolution of permeability around the drift.