METHOD OF PILLAR BREAKING UNDER CONDITIONS OF HIGH ROCK PRESSURE Russian patent published in 2003 - IPC

FIELD: ore mining industry, methods of ore breaking by drilling and blasting operations; applicable in ore deposit mining under conditions of high rock pressure. SUBSTANCE: method of pillar breaking includes drilling of borehole rows, charging and blasting of boreholes. In course of short-delay blasting, imparted to ore pillar, in horizontal section, is shape of one sheet hyperboloid of rotation with permissible minimum thickness whose value is determined by formula given in invention description. Boreholes on side of bare pillar are located over generating line of hyperboloid of rotation and charges of these boreholes are blasted by short-delay method, for instance, every other one. Boreholes along pillar axis are located rectilinearly in one row with charge weight rising from center to flank of pillar and blasted in the last. EFFECT: higher quality of ore crushing, reduced consumption of explosives, volumes of drilling operations and borehole losses in block provided safety for workers drawing rock from block. 2 dwg