The paper presents results of conducted research using regional and local methods of forecast and control over geomechanical state of the rock mass at burst-hazardous Nikolayevskoye field, located in a geodynamically active region. The study subject is the ore mass of Nikolayevskoye field, characterized by man-induced and tectonic disturbances and high geodynamic activity. The aim of research was practical implementation of methods and instruments of forecast and control over geomechanical state of the burst-hazardous rock mass and safety improvement of mining operations. Exploitation practice of burst-hazardous fields demonstrates that forecast accuracy of hazardous rock pressure demands cutting-edge multi-level systems, where local methods and tools complement regional ones. A regional forecast of rock-burst hazard at Nikolayevskoye field was performed by means of seismoacoustic method using automated control system for rock pressure (ACSRP) «Prognoz-АDS». Local forecast was carried out using «Prognoz-L» device, geophysical (sample disking) method and visual observations of dynamic pressure manifestations in the mining tunnels. Quality assessment of stress-strain and burst state of the rock mass was performed using specialized software «PRESS 3D URAL». Integration of engineering and geomechanical data in the process of conducting research guarantees a relevant assessment of rock-burst hazard in various areas of the field at various stages of its development. Practical verification of the system, where local methods and tools complement regional ones, demonstrated satisfactory results at Nikolayevskoye mining plant, which makes it recommendable for other mining facilities extracting ore at great depths under similar conditions of active geodynamic processes.
The subject of the research is the stress-strain and rock burst hazardous state of the ore massif of the Nikolaevskoe polymetallic deposit, formed under the influence of complex mining-geological and mining-technical factors. The purpose of the research is to establish the peculiarities of the formation of technogenic stress fields at the deposit, which is characterized by a block structure, a complex tectonic system and the presence of a large volume of developed spaces. Volumetric geodynamic modeling of the stress-strain state of the massif at different stages of the development of the deep horizons of the deposit was carried out by collecting information on the structure, properties and geodynamic state of the rock mass. The assessment of stress changes taking into account the effect of hypsometry, the configuration of the selvages, the physical-mechanical properties of the ore deposit and host rocks, the presence of tectonic disturbances was made using the developed numerical algorithms, the automation equipment of the initial data and the PRESS 3D URAL software. The simulation made it possible to establish that tectonic faults in the massif lead to a qualitative change in the stress-strain state in certain parts of the ore massif and in the pillars, namely, the reduction of stresses along the tectonic faults and their growth in nearby pillars. The identified features of the distribution of stresses in the tectonically disturbed rock massif of the Nikolaevskoe deposit will allow to identify in advance potentially hazardous areas both at the planning stage of mining operations and during development, as well as to work out effective rock burst measures to increase the safety of mining. The results of research can be used in enterprises with similar mining-geological and mining-technical conditions.
Regularities of forming of strained – deformed state in elements of designed variants of systems of development on various mining stages for Nikolaevskoe and Yuzhnoe polymetallic deposits are determined on the results of numerical modeling. Analysis of technogeneous stress field made it possible to discover some potential burst-hazardous sections of the rock massif and to substantiate effective rock pressure decreasing measures for preventing dynamic rock pressure occurrences.
