UNDERGROUND DEVELOPMENT METHOD OF TECHNOGENIC DEEP-LYING GRAVEL DEPOSITS OF PERMAFROST ZONE Russian patent published in 2012 - IPC E21C41/22 E21F15/00 

FIELD: mining.

SUBSTANCE: development is performed during winter period. First, vertical through wells with diameter of 0.5-0.6 m are drilled from surface above developed mine field, through which ice-water mixture is supplied; ratio of solid phase to liquid phase is 1:3 by volume. Filling mass is erected layer by layer; at that, each layer is frozen with forced blowing using cold atmospheric air from blowdown fan. Thickness of a single layer |N_layer| is determined from the following ratio: N_layer=1.5|t_amb.|-20, cm, where: 1.5 and 20 - constant coefficients; |t_amb| - absolute monthly average ambient air temperature of months during winter period, °C.

EFFECT: invention allows reducing the time required for stowing operations and improving the stowing quality.

2 dwg