Modelling fracturing process of geomaterial using Lattice Element Method

Fracturing of geomaterial is involved in many geological processes and engineering applications. However, modelling of fracturing process is considered challenging owing to the heterogeneity of geomaterial. In this paper, a simple three-dimensional discontinuum method Lattice Element Method (LEM) is introduced to simulate the fracturing process. Geomaterial is modelled as interconnected 1D spring elements. Fracturing is modelled by simply removing lattice element exceeding a specified threshold related to the critical energy release rate of rock. Mesh dependency phenomena can be manipulated by introducing disorder in model which also incorporates heterogeneity in model. An in-house C++ code using a parallel conjugate gradient solver has been developed which is capable to handle large scale model composed of millions of lattices. Three simulations of fracturing process of a geomaterial with a pre-existing penny shape crack under uniaxial tension are presented. A simple discretisation of domain into 1D springs and the use of efficient solver enable LEM to model the heterogeneity of geomaterial by including large amount of rock features such as faults and joints inferred from geophysical surveys. This can shed light on explaining the complicated fracture patterns observed in brittle geomaterial. © 2015 Taylor & Francis Group.