Forecast of the geomechanical state of the rock mass in difficult mining and geological conditions based on in-situ test data

In order to support production processes at the Oktyabrsky deposit of rich sulfide ores at a depth of 2000 m two exploration workings were driven in 2020-2023 at the Levels of -1650m and -1750 m. with a length of about two kilometers each. In order to provide ongoing mining operations with a forecast of the geomechanical state of the rock mass, field studies were performed in advanced boreholes using ultrasonic logging (UL), borehole telemetry, and core disking. The UL method is used to study the elastic properties and fracturing of rocks. The fracturing of the bore of the advanced boreholes and the presence of various geological and structural heterogeneities are estimated by the telemetry method. The core disking method is based on the ability of hard rocks to brittle fracture. It is established that the vector of the main compressive stresses acts in the rock mass of the studied workings in different directions. Individual cases of identifying the core disking zones and "tracks" on the periphery of the advanced boreholes are not representative in their parameters for classifying these sites as "rock bump hazardous". Thus, a combination of the obtained data proves the efficiency of the applied forecast of the geomechanical state of the advance boreholes, while the information on the geomechanical state of the rock mass in the vicinity of the advance boreholes made it possible to timely make recommendations regarding the mining prcedures in order to ensure the stability of the workings being constructed.