Rymarchuck B. Development of resource saving technology of underground blasting of hard and extremely hard iron ores.

Dissertation is devoted to the solving of the problem of underground brekage of hard and extremely hard ores using during the breakage vertical concentrate charges and the simplest without trilita Explosive - igdanite of high pressure (IHP-5). Optimum structural parameters of the vertical concentrate charge of Explosive (attitude of charge height toward the diameter) relative height of air bag and rock cushion were found. Parameters of technology of formation of the screen by the shooting of the sheaves of deep mining holes were defined. The parameters of screen were found: thickness and distance to the charge, which secure a maximal reflecting effect of waves of tension to the side of the breaking massif. An effective location of the charge in the block was found - "the center of equal effective action of explosion", in which the explosion of charge secures equal tension on all bared surfaces and accordingly high quality of crushing. The technology of production of the simplest Explosive (igdanite ofhigh pressure IHP-5) was developed, that provided with the high physical stability and explosive properties. The technology of working off the deposits with the breaking of the massif by the Explosives HCE and preliminary delineation of the screen block was developed.