Rockburst hazard potential assessment of rocks of the Khibiny massif deposits according to the Kaiser criterion

The mining and geological conditions in the mines worsen due to changes in the stress-strain state of rock masses and their structural disturbance when mining goes to great depths. Under such conditions, it is necessary to assess the impact hazard of ores and rocks that make up the mined deposits. For the prompt implementation of such an assessment, it is proposed to use the Kaiser criterion consisting in the analysis of experimental data obtained on rock samples. The paper presents the results of laboratory testing of rock samples from the deposits of the Khibiny massif under uniaxial compression and tension. The values of their brittleness coefficients have been determined. The possibility of using the Kaiser criterion for a preliminary assessment of rock burst hazard potential has been shown. It has been established that spotty-trachytoid melteigite and trachytoid ijolite-melteigite have a high potential for impact hazard, while spotted apatite-nepheline ore does not have such a potential. A comparison has been made of the obtained results of rockburst hazard assessment of hard rocks from the Khibiny massif deposits according to the Kaiser criterion, as well as the criterion of the Mining Institute of the KSC RAS and the criterion of A. N. Stavrogin. It can be noted that the Kaiser criterion makes it quite easy to carry out a preliminary assessment of rock burst hazard based on the results of testing samples on standard presses. However, to increase the degree of reliability of the data obtained, they must be certified according to the criterion of the Mining Institute of the KSC RAS or the criterion of A. N. Stavrogin.