Abstract
Purpose. The research is aimed at developing scientifically sound principles of the technology for maintaining mine workings to ensure their stability during mining of coal seams in the Karaganda coal basin (Republic of Kazakhstan). The influence of fastening parameters on strengthening effect under conditions of controlled stress-strain state of the “host rocks – fastening elements” system is studied. Methods. The study includes an analysis of scientific-practical experience in operating mine workings and conditions for conducting underground operations. The stress-strain state of the mass is assessed by the finite element method in two-dimensional formulation using the RS2 software package. The inelastic deformation zones are calculated taking into account the geological-technological factors influencing the behavior of the mass in the area of the cutting zonal extraction workings. Findings. For the first time, the patterns of change in the sizes of plastic deformation zones and stressed areas around mine workings with different technological fastening solutions have been quantified. The dependence of the stress-strain state on the characteristics and geometry of the fastening system has been revealed. Originality. The patterns of changes in the size of deformation and stress zones in the vicinity of mine workings at different techno-logical fastening schemes have been determined. The dependence of the stress-strain state of the mass on the parameters of the fastening systems has been revealed. Practical implications. Scientifically sound recommendations have been developed for the technology of fastening cutting ventilation mine workings using two-level roof-bolting systems in the case of stable roof layers. The optimum parameters for fastening operational mine workings that provide stability at different depths of seam occurrence have been substantiated.