Forecast of potential rockburst hazard during the reconstruction of the Yugo-Zapadnaya mine at the Darasun deposit
Research aim is to study the geomechanical conditions of the Yugo-Zapadnaya mine at the Darasun gold ore deposit during the reconstruction of mining to forecast the rockburst hazard. Methodology. Laboratory tests of physical and mechanical properties of rocks were carried out. The initial stress-strain state of the rock mass was assessed by natural measurements and by solving the inverse geomechanical problem. The method of finite element analysis determined the technogenic stresses in the structural elements of the geotecnologies. Engineering calculations of critical depths of rockbursts were performed. Results and conclusions. By results of researches it is established, that the natural field of in-situ stresses in the deposit array of rocks is distributed discretely: high-stress, medium-stress and off-load zones are distinguished. The rocks have high strength and elastic properties and are prone to brittle fracture. The actual mining has reached critical depth of rockburst. Air headings and ceiling are in the most hazardous state. To increase the safety of mining, a set of measures has been proposed: unloading roof ceiling and corners with slots, giving the roof a hipped shape, replacing the ceiling with a concrete pillar. It is recommended to conduct operational geomechanical monitoring at the mine.