ABSTRACT
The paper presents the investigation results on changes in the rock mass state during mining under rockburst-hazardous conditions. The authors interpret the results of comparing the cluster analysis of seismic events and numerical modelling of stress state in the rock mass on the case study of the apatite-nepheline deposits located in the Khibiny rock massif (Murmansk region, Russia). A case study object has been chosen a rock block 7/10 from mining level +170 m, the Kukisvumchorr deposit.
The authors have identified clusters of seismic events, associated with different rock mass regions. The 3D modelling of the stress-strain state was carried out taking into account the initial stress-strain state in the rock mass; a mountainous relief; the characteristics of enclosing rocks, ore body and faults; and actual conditions of mining operations. The authors have revealed the correspondence of identified stress concentration zones and zones of increased seismic activity and determined a focal zone of a large seismic event.
The study demonstrates that the comparison of seismic monitoring results with numerical modelling of stress-strain state in the rock mass allows better assessing the geomechanical state of the rock mass, determining a cause of hazardous dynamic events, and improving the assessment quality of potentially rockburst-hazardous zones at the mine planning stage.
