The work considers the problems of recurring mining of lost ore reserves. Recurring development of deposits contributes to the improvement of the subsoil use completeness. Primary development is based on the method of maintaining overlying rock and stoping zone, whereas under the recurring excavation it is usually necessary to meet significant integrity damage of ore massif and enclosing rock. For this reason the production of the lost ore reserves with traditional methods is near-impossible. When selecting the method of underground recurring development it is necessary to take into account the factors which determine the practicability of these works: when excavating ore with low content of metal the factor of production cost acquires crucial importance; in case of works in the disturbed massif, the factor of safety is especially important; works in disturbed zones requires significant resources to develop and maintain the workings, thus, the method of development has to provide significant production output. By way of example of lost ore production, brand new technology is suggested, the essence of which consists in the additional output of caved rock mass out of the stopping zone in heavy suspensions.
Geological and geomechanical factors, which influence the choice of stoping technology in rock-bump hazardous conditions, are studied thoroughly enough. By their complex influence the choice of deposit underground mining system class and development system structural components parameters are determined. Investigations over the development of mine engineering model of rock breaking allowed formulating the requirements to rock-bump safe technology. Knowing the reasons for statistic and dynamic loadings origination, it is possible to realize the most favorable regime of their manifestations, using manufacturing methods of mining. The technology has been tested at the shafts of the North Urals Baxite Mine, multilevel system of chamber mining under artificial roof is introduced. The new technology exploitation and application when mining ore bodies in rock-bump hazardous conditions and unstable enclosing rock allowed increasing the safety of works as the result of operating stresses value reduction by means of advance mining of the ore body in the hanging wall.
The problems of system development with a chamber extraction and filling when mining ore reserves with low strength properties for example mine “Aikhal” are considered. Several aspects have been justified, including the advantages of the chamber system of development with “checkerboard” order mining stocks: no need for haul ore mines in the array; drilling and filling ort in the chamber is located in the ore mass directly under the base layer of filling mass; in such conditions, the stability of the walls and roof of the unit vector is safe and does not require mounting arches (provides there is anchorage); shipping ore and drilling of mines are carried out at different levels (horizons) when it becomes possible to combine the drilling and loading time within one of the recessed chamber and increases the intensity of the ore in the chamber; airing during mining operations can be performed using common mine jet with free movement of air through the chamber, thus eliminating the need for ventilation of blind workings using VMP through the ventilation sleeves. Technology of the chamber system development with the “checkerboard” order of processing and the filling of a goaf was recognized in 2013 as an invention. Currently this technology is being tested at the mine “Aikhal” of “ALROSA”.