Simulating hydraulic fracturing preconditioning in mines with the material point method

Hydraulic Fracturing (HF) is becoming increasingly popular as a candidate mechanism for preconditioning rock mass in mining. To date, accurate numerical methods for simulating the complex behaviour of fluid-driven fracture network near excavations are not well established within the mining industry. In this work we propose a novel implementation of the Material Point Method (MPM) to simulate the complex HF sequence followed in mining; this creates a dense network of fractures. We present a new way of generating fractures in the context of the MPM framework by incorporating the so-called Marching Cubes algorithm into the computational background grid. We first validate our model against some laboratory verified results and then apply the method to some conceptual models. These experiments illustrate effective ways of preconditioning with HF to ensure that stress is modified around the fractured area and the associated seismic hazard thereby reduced.