COMPLEX GEOMECHANICAL SUBSTANTIATION OF THE OPEN PIT HIGHWALL SLOPE ANGLES

This paper presents the results of the complex of geomechanical researches for substantiation of stable slope angles of the open pit, including testing of physical and mechanical properties of rocks, investigation of structural composition the rock mass surface, determination of the MRMR rating values, zoning of the open pit surface according to Prof Laubscher 's classification. Based on the obtained results the values of the bench, face angles were recommended, and the measures to ensure its stability were developed. Classifying the surface of the pit enabled to identify the factors that have the most negative impact on the surface rock mass. It was found that the influence of some factors can be significantly reduced making possible to increase the values of the bench face angles while maintaining sufficient safety of mining.