METHOD OF MINING OF THICK DEPOSITS IN UNSTABLE MASSIF Russian patent published in 2002 - IPC

FIELD: mining; applicable in underground mining in unstable massif. SUBSTANCE: method includes mining of ore body by continuous breakage face with no pillars; driving of development and subordinate development workings. At least one compensating cavity is formed at initial period by breakage of ore with explosive charges in a set of holes onto cutoff rise working, and ore is drawn out. As size of compensating cavity rises and stability of its walls reduces, partial drawing of broken ore within 20-30% of its volume is performed after ore breakage by explosive charges in a set of holes onto rise working. Remaining broken ore is shrunk in compensating cavity, and further breakage of ore for expansion of cavity is carried out on shrunken ore. Cavity is fully filled with broken ore by the last design set of explosive charges. To form next compensating cavity, prior to ore breakage, shrunken broken ore is loosened in compensating cavity by drawing shrunken ore in amount of 25-40 vol.%. Further breakage of ore of block mass is effected by torpedo distributed explosive charges located in rises onto loosened shrunken ore in compensating cavity and on clamped medium. Then whole broken ore is drawn out of block. EFFECT: provision of safety in operation by provision of conditions for prevention of compensating cavities from caving. 4 cl, 7 dwg