Case study of hydraulic fracturing for coal burst risk mitigation

Abstract

Abstract Coal bursts pose significant safety and operational challenges in deep mining environments, necessitating effective mitigation strategies to address high-stress concentrations and dynamic failure risks. This study evaluated the efficacy of hydraulic fracturing as a preconditioning tool at a longwall face of the Mengcun coal mine with strong coal bursts, Shaanxi Province. The program involved the systematic creation of a fracture network through high-pressure fluid injection, monitored via microseismic arrays, stress measurements, and hydrological sensors. Results demonstrated that hydraulic fracturing effectively redistributed in-situ stresses, reducing high-stress concentrations by up to 30%, lowering the frequency of high-energy microseismic events, and enhancing the stability of fractured zones. However, the presence of unfractured blind spots and interactions with pre-existing faults highlighted the need for optimized well placement and adaptive fracturing designs. These findings underscore the potential of hydraulic fracturing as a critical preconditioning tool in high-stress mining operations, which could provide a framework for improving safety and efficiency in similar geological and operational settings.

Keywords

• Deep coal mining
• Coal burst
• Hydraulic fracturing
• Case study