PROCESS OF ARRANGEMENT OF HIGH WALLS IN OUTLINE OF STRIPPING Russian patent published in 2004 - IPC

FIELD: mining industry, open cast development of deposit. SUBSTANCE: process of arrangement of high walls includes drilling of line and breaking holes, charging and blasting of breaking holes, shipment of rocks. First dummy holes of line row are drilled to height of wall at distance of 100-400 diameters of holes away from blocks of mass blasts and with distance of 2-3 diameters of hole between holes. Then buffer inclined holes are drilled at distance of 10-14 diameters of holes over surface and at distance of 4-5 diameters of holes away from line row of holes in lower part. Distance between buffer holes in row is 4-6 diameters of holes. Then breaking holes are drilled in first working subshelf. Buffer inclined holes with distributed charges including three charges, upper, center and lower, securing crushing of rock intervals between inclined and line rows of holes and section of rock interval between line row of dummy holes brought together with density of charges 3.0-3.5, 2.5-2.8, 1.0-2.0 kg/r m in upper, center and lower part of inclined holes correspondingly are first charged and then blasted. Thereupon breaking holes are charged and blasted with short delay by rows, rock is shipped from upper working subshelf. At final stage operations of drilling breaking holes, their charging, blasting and rock shipment from face of second working subshelf are carried out. EFFECT: enhanced stability of high walls thanks to decreased disturbance in mass near line. 3 dwg