THE REGULATION OF MINING MODE ON DEEP OPEN PITS OF LARGE EXTENTION WITH THE APPLICATION OF MULTIBENCH STEEPLY INCLINED TEMPORARILY INOPERATIVE QUARRY SIDES

Abstract

In the paper the necessity and expediency of increasing the slope of the working sides of deep quarries has been substantiated as a mean of regulation of mining operation mode. It has been established that one of the most effective ways to regulate the mining regime on deep quarries of considerable extension is the implementation of bench-shaped steeply inclined temporarily non-working quarry sides, developed by the Institute of Mining of the Ural branch of the Russian Academy of Sciences, which are characterized by effective methods of their formation and depreservation, including favorable conditions for opening and safety of mining operations under rock-fall conditions. A method of calculating the appropriate parameters of the sides – their height and width of each ledge – has been developed and tested. As a result of statistical studies, it was found that the main factors determining the economic efficiency of field development with the implementation of temporarily non-working sides of
the developed design are: the depth of the quarry, the number of benches and the rate of decline in mining operations during its reopening. The economic effect in the form of reduction of discounted costs for the development of the field by means of use of this regulation method for the mining regime with a significant depth of quarries can reach 3.5 – 4 %.