EVALUATION OF NATURAL STRESS OF ROCK MASS OF TSENTRALNOE AND RADUZHNOE OREBODIES OF KONEVINSKOYE GOLD DEPOSIT

Abstract

The paper presents the results of geomechanical studies of the Konevinskoye gold ore deposit located in the southwestern part of the Khuzhirskoye ore field within the Sailaga granodioritic rock mass. The main reserves of mineral resources are narrow steeply dipping veins. In 2011-2014 the works were carried out to study the geomechanical conditions and to determine the natural stresses on the lower horizons. The following basic geomechanical factors on the investigated depths influencing the regularities of distribution of natural stresses have been established: heterogeneous cryogenic state of the rock mass, presence of local areas of natural-dry and water-flooded rocks, complex tectonic structure of the deposit, mountainous terrain of the earth's surface. The laboratory tests of physical and mechanical properties of rocks and ores have been carried out. The following parameters have been identified: compressive strength, tensile strength, adhesion strength, angle of internal friction, shear strength, Protodyaconov's strength index, average density, Poisson's coefficient, Young's module. The natural stress values have been measured at the Konevinsky and Raduzhny sections (Tsentralnoye and Raduzhnoye orebodies) using the method of slotted unloading based on the technique of the Institute of Mining, Ural Branch of RAS. The relations between vertical, horizontal longitudinal and horizontal transverse stresses have been established. The obtained regularities of natural stress distribution were used as boundary conditions for determining the parameters of underground geotechnologies at the mine during the development of "Temporary guidelines for determining the parameters of stable pillars and outcrops of mine workings and stopes of Konevinsky and Raduzhny sections at Konevinskoye deposit".