FIELD: mining engineering.
SUBSTANCE: open pit mining method for deep laying deposits with the use of temporarily nonactive walls coprises a horizontal platform formed under steep angle close to the maximum at the level of the upper mark of the temporary nonactive wall and divided during depreservation of a wall into separate blocks, including rock material prepared or ready (blasted) for the excavation. The blocks are mined out with draglines installed on backs of the mined-out ledges with unloading of the rock mass into vehicles located at the same level and which haul it to the surface via declines located on the final open pit wall. The height of the mined-out ledges and the width of the cuts are taken from the working parameters of the excavators (depth and radius of scooping), the ledges are mined 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
