FIELD: mining engineering.
SUBSTANCE: open pit mining method of deep laying deposits with utilisation of temporarily nonactive walls it is formed at a steep angle close to the limiting one. At the upper mark level of the temporary nonactive wall a horizontal pad is left and divided into separate blocks along the length including ready (blasted) ones and the ones prepared for rock mass excavation when the wall is depreserved. The blocks are mined out with hydraulic back-shovel excavators mounted on the roof of the mined benches with loading rock mass into vehicles at the same level and transportation to surface via declines located on the end wall of the pit, the height mined benches and entries width are taken based on the working parameters of the excavators (depth and radius of excavating), benches development is carried out layer by layer from top to bottom. When advancing mining blocks of the active bench to the sufficient dimension and ensuring cargo and transportion connection with the surface, parallel development of the next bench starts, and so on until the entire temporarily nonactive wall is depreserved. To protect benches located below the temporary nonactive wall against rock falls a rock protection area is built at its base along the entire length, including a platform for placing the falling rock mass, an embankment on which a hydraulic backhoe-type excavator is placed, and a transport platform. The rock mass falling on the rock protection area is loaded with hydraulic excavator into vehicles and transported to the surface. As the mining operations go down the rock protection area is moved to lower elevations, providing the possibility to increase height of temporary nonactive wall and the preservation volumes.
EFFECT: decrease of current stripping coefficient within initial period of deposit development.
3 dwg
