STUDY ON CROSS-SECTION PARAMETER OF SUBLEVEL CAVING WITHOUT FLOOR PILLAR DRIFT IN GONGCHANGLING IRON MINE

Based on the Gongchangling underground iron mine whose part of ore body has the characteristic of thin thickness,large slop angle,bad bottom wall,only one drift which can't form the lozenge disposition,and drift can't approach bottom wall.thus,all of these lead to increase the waste rock rate and reduce ore recovery rate,and at the same time lead to ore depletion ahead of being extracted.In this paper,drawing theory,physical simulation and computer simulation and industrial experiment are be used on studying drawing ore,and drawing a conclusion that ore recovery rate can be increased largely by enlarging extracted ore drift cross section.