ERECTION METHOD OF PROTECTIVE CUSHION ABOVE DEVELOPED VERTICAL ORE BODIES UNDER PERMAFROST ZONE CONDITIONS Russian patent published in 2014 - IPC E21C41/00 

FIELD: mining.

SUBSTANCE: at the bottom of the developed open pit there created is a freezing circuit by driving of zigzag-shaped trenches and laying of pipes in them; after that, ice rock backfill is erected by freezing-out overburden; a waterproof screen is laid and filled with a clay loam layer. Then, an upper freezing circuit is made of pipes and a heat-insulating layer of local loose materials, a waterproof screen and a clay loam layer is erected on it and covered with overburden. As a protective cushion is being created, cold air is delivered via lower freezing circuit, and cooled air is supplied via upper freezing circuit during warm season.

EFFECT: providing insulation of underground work against penetration of surface water and dynamic actions under permafrost zone conditions; providing safe work performance.

2 dwg