METHOD OF DRIVING IN CAVED ROCKS OF MINE WORKING Russian patent published in 2002 - IPC

FIELD: mining; applicable in emergency driving in caved rocks of mine workings, for instance, after explosion of methane-air mixture, sudden outbursts, etc. SUBSTANCE: method includes introduction into caved rocks of perforated injectors-sprinklers and freezing columns; injection into empty space of water and/or plugging filler and formation of ice-rock barrier by freezing of caved rocks with cryogenic fluid. Made in place of formation of ice-rock barrier, over contour of working, is niche from which freezing columns and perforated injectors- sprinklers are introduced into caved rocks from exterior side of working cross- section perimeter. They re introduced into concentric rows with location of freezing columns in internal row, and perforated injectors sprinklers in external row. Perforated injectors-sprinklers are located beyond formed ice-rock barrier at distance from freezing columns determined by formula where R is distance between exterior row of injectors-sprinklers and internal row of freezing columns, m; H is calculated thickness of wall of ice-rock barrier, m; L is distance between freezing columns, m. Then, sides of working are coated through picks-injectors with phenol foam plastic to coat caved rocks with subsequent injection through injectors-sprinklers of water cooled with liquid nitrogen into rocks caved down. Water is frozen with low-temperature liquid nitrogen to form ice-rock barrier under whose protection, working is driven with removal of muck. EFFECT: reduced unproductive expenditures and improved safety due to increased strength of foam plastic and ice-rock barrier formed in caved rock mass. 2 dwg