STUDY OF PARAMETERS OF DEVELOPING THE DEEP KIMBERLITE OPEN PITS BY STEEPLY INCLINED AUTOSLOPES

Abstract

The paper considers the technological scheme of transition to a steeply inclined opening with the use of fourwheel drive dump trucks during the mining of kimberlite quarries. It proposes analytical method of calculating the amount of additional dressing of pit from the placement of transportation and communications of the angles of slope inoperative boards by the opening of the quarries whit spiral shaped autoslopes. As a result of the modeling, the regularities of the change in the additional spacing of the sides depending on the depth of the quarry, the width and the slope of the road ways, as well as the power of the ore body have been established. The technique of the optimal depth of transition to a steeply sloping opening has been developed. It is noted that the efficiency of the transition to the developing by steeply inclined driveways, estimated at reducing the above costs for the development of the field, depends on the slope of the opening workings, on reducing the volume of separation of the sides of the quarry, on the power of the ore body, on the cost of stripping and the cost of transportation of rock mass by fulldrive dump trucks and dump trucks with a wheel formula 4×2, as well as their ratio. The regularities of the changes in the given costs for the development of deposits depending on the depth of the transition to the steeply inclined opening is extreme. The optimal depth of the transition to a steeply sloping opening is characterized by relative stability, amounting to 54-60% of the design depth of the quarry. The results of the study have their implementation by the Institute "Yakutniproalmaz" at pro-design pit "Nyurbinsky" to a depth of 750 m.