Numerical Modelling of Stress-Strain State Evolution of Rock Mass with Underground Openings: Triggering influence of Mining at Different Horizons

Abstract

On the base of a quite simple structural model of a rock mass, containing coal seams on two horizons, the numerical modelling of coal mining is carried out. A finite difference numerical technique is applied. At first mining starts at upper horizon and then moves to lower horizon. It is shown that mining process at lower horizon has a significant triggering influence on a growth of damage zones in roof and floor at upper horizon. The features of spatio-temporal migration of deformation activity are studied numerically. The foci of a largescale fracture is located on the border of seismic silence zone and the zone, where the deformation activity migrates. This border also has another characteristic - the maximum gradient of the rock pressure is observed in this zone.