Coal pillars role in rockbursts occurrence in underground coal mines in the USSR

The mining of coal seams prone to rook bursts should be carried-out with no leaving the pillars, where it is possible. The most hazardous,in rock burst manifestation, appear to be the pillars being left for protection of the permanent and development workings. The timely determination of tendency to rock bursts offers an advantage in the design stage or reconstruction of coal mines to choose the optimal method of the coal seam uncovering with due account of its hazard in rock burst occurrence and to prepare the seam to mining that will permit to minimize the number of pillars to be left within the mine field. The methods of uncovering and preparation of coal seams, allowing to reduce the number of pillars, will be defined to a great degree by geological conditions of coal deposit and by mechanical properties of coal.