OPTIMIZATION OF PARAMETERS OF DRILLING AND BLASTING OPERATIONS AT QUARRIES OF A LARGE-BLOCK STRUCTURE

Abstract

It has been established that when exploding large- and very large-block arrays, the blockiness (fracturing) of the array is the main carrier of the explosion energy, and the quality of crushing largely depends on the heterogeneity of the medium. In large-block massifs, cracks of different shapes and widths filled with rocks with low acoustic rigidity (intervening rocks) divide the mountain massif into separate blocks, which makes it difficult to regulate the degree of rock crushing by an explosion. It is generally accepted that the specific consumption of explosives is the main technological factor in regulating the quality of crushing, and regardless of the physical and mechanical properties of the exploding array, an increase in the specific consumption of explosives leads to an improvement in the degree of crushing of the rock. However, the regulation of the quality of crushing in fractured rocks with a change in the specific flow rate of explosives is very limited.

A method is proposed for optimizing the parameters of drilling and blasting operations in quarries of large-block structures, by selecting multi-power explosives (explosives), taking into account the size of cracks, as well as the nature of their distribution in the rock mass. Depending on the nature of the distribution of inhomogeneous rocks, the uniformity of the distribution of the explosion energy in the depth of the array is determined (the choice of the design of the explosive charge, the type and length of the explosive).

The results of industrial explosions are presented, confirming the improvement of the quality of crushing at the quarry of building materials for the production of crushed stone. The proposed method can be applied to non-metallic construction quarries of a large-block structure, as well as on complex-structured faces of an ore quarry.