The Numerical Analysis of Fault-induced Mine Water Inrush Using the Extended Finite Element Method and Fracture Mechanics

Fault activation caused by construction, earthquakes, or mining can produce disastrous water-inrush episodes in underground mines. Fault activation is generally caused by stress concentration at the fault tip, so in this study, a computational model of a typical underground stope with a hidden fault was established for quantitatively assessing the magnitude of the stress concentration of the stress fields of the fault-tip. Numerical simulation was performed using the extended finite element method and fracture mechanics. The stress intensity factors, which represent the magnitude of the stress concentration, were obtained using the interaction integral method to quantitatively evaluate the tip fields and to assess the possibility of fault activation. The mining depth, fluid pressure, fault dip, and fault length were analyzed to determine their effect on fault activation. In addition, the advance of a working face was simulated in the same computational model to determine whether underground mining would cause fault activation.