The article is devoted to the problem of maintaining and increasing the volume of ore mined during the conversion of mining from an open-pit mining method to the underground mining method. The increase in production volumes and the need to use powerful drilling and handling equipment when using development systems with the collapse of rocks and ores requires a change in the height of the beaten layer of ores and the parameters of the output workings. This is associated with an increase in the risk of labor for working face miners.
The aim of the work is to minimize the danger to miners by optimizing the parameters of technological processes with coordination in time and space. The goal is achieved by conducting field and laboratory research with the involvement of best practices.
The results of studies of the main aspects of the problem under consideration are presented, including ensuring the stability of the twin outlet workings depending on the height of the ore bed being beaten at increasing the completeness of extraction with an increase in the front of ore output for the twin workings. The results of studies in the field of modeling the parameters of breaking and ore production with an increased height of the beaten layer are presented. Dependencies are obtained between the depth of work, the height of the beaten layer and the stability of the massif, as a guarantor of miners safety. Substantiation is given concerning the possibility and preference of ore output to dual workings with a sub-floor height of at least 12.5 m. This reduces the number of breaking cycles of the same ore volume. Optimization of the organization of the second working reduces the risk of injury to the workers of the face during a set of works regulated by safety rules to bring output and supply mine workings to a safe state after blasting operations. It is proved that increasing the height of the beaten layer optimizes the working conditions of explosive charges in the massif, comprehensively improving the blast data.