PROTECTION METHOD OF REUSABLE DEVELOPMENT WORKINGS Russian patent published in 2013 - IPC E21D11/00 

FIELD: mining.

SUBSTANCE: protection method of reusable development workings involves performance of development workings, installation of several cylindrical wooden-and-concrete blocks on each other to the whole thickness of the extracted formation at the interface of face with development working; at that, wooden-and-concrete blocks are installed with pre-stressing by arranging a pneumatic cylinder between them in hollow cylindrical block. Then, compressed air is supplied to pneumatic cylinder and wooden-and-concrete blocks are pre-stressed between side rocks, and after roof rocks are lowered and all wooden-and-concrete blocks contact each other under action of overburden pressure, pneumatic cylinder is removed to development working, and a missing part is installed in its place till full volume of flat cylindrical block is obtained.

EFFECT: improving protection efficiency of reusable development workings by installing a support with pre-stressing at the interface of working face adjacent to development working.

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