An assessment of multiple seam stress conditions using a 3-D numerical modelling approach

The paper presents results of 3-D numerical modeling by a finite element method of the stress condition of the rock massif when undermining the flat thick coal seam. As a result of the executed research, the authors establish influences of the pillars left between longwall panels in previously mined top seam 70 on distribution of stress in the current mining seam 69. The need for application of 3-D numerical models to take a note of imposing the bearing pressure of a longwall and the increased stress from the pillar is shown. Recommendations on the location of entries of the longwall panel when undermining the coal seam are made. (paper)