DEVELOPMENT OF THE MECHANISM OF ACTION OF DECONCENTRATED CHARGES OF VARIOUS SHAPES FOR VARIOUS MINING CONDITIONS

The modern requirements of the market economy and the increasing complexity of the field development conditions require new scientific and technical approaches in deep quarries and mines in the complex development of subsurface resources. As you know, the dominant mining paradigm in drilling and blasting is associated with the technique of drilling wells and boreholes of a circular shape (cavity) with the placement of explosives in it. However, in mining science and practice, the variety of mining conditions has long required the creation of methods for the destruction of rocks with an asymmetry in the distribution of explosion energy in space and its maximum concentration in certain directions. In this regard, we consider a conceptual direction based on a fundamentally new mechanism of action of the explosion of known groups of parallel-converged borehole charges, which effectively expand their use in various mining applications. The development of a new mechanism of action of the explosive process with the use of a computer program and numerical simulation of calculations made it possible to use the change in the shape and design of the charge as a means of increasing the share of the energy flow of the explosive explosion in a certain direction. The design of the deconcentrated charge is shown as a means of increasing the fraction of the energy flow of the explosive explosion in a given direction, which leads to a significant increase in the efficiency of the directed explosion and, in particular, minimizes its action in the opposite," legit", direction. Based on the results of the research, a method of blasting operations is proposed to neutralize the influence of anomalies in the state of the massif on mining operations by the explosive method. The method includes the appropriate tools, characterized by an unconventional design of the borehole charge and using a mechanism for influencing the anomalous states of the array with a combination of its explosive features.

TECHNOLOGICAL DIRECTIONS AND ECOLOGICAL ASPECTS OF AMMUNITION DISPOSAL IN MINING ENTERPRISES OF UKRAINE

The chronology of formation of ammunition disposal with expired shelf life is considered. The characteristics of ammunition utilization technologies developed in Ukraine are given, their shortcomings are pointed out. Data on emissions of toxic compounds into the environment due to the implementation of domestic technologies are presented. There is a lack of state control over environmental pollution by toxic compounds during the disposal of various types of ammunition. At the same time, the problem of creating a charge from the PSU, which allows the disposal of ballistic checkers (BС) using them without prior grinding, while increasing the safety of loading. A method of forming a borehole charge of explosives from military ammunition for mass explosions by creating in the core of the well the transfer of detonation to each part of the charge, made of bundles of ballistic checkers, which will ensure the completeness of the initiation of the entire charge and thereby improve the quality of crushing rocks in the lower part of the ledge (sole), reduce the effects of seismic waves, especially on residential buildings, while disposing of ammunition. The developed technique of conducting mass explosions pursues two goals, one of which is aimed at preparing the rock mass for extraction at opencast mining with low-cost explosives, and the second, no less important, solves the problem of disposal of expired ammunition. It is clear that the third no less important goal is lined up for this technology - to provide the technology of economically attractive utilization of BP with new environmentally efficient technological solutions.

DETONATION OF A LOW-DENSITY EMULSION EXPLOSIVE

One of promising directions in conducting sparing highly mechanized blasting operations in open-pit mining may be the use of low-density emulsion explosives sensitized with light porous granules made of low-strength material (for example, granules of polystyrene foam). Experimentally, it was possible to show that such explosives allow mechanized charging into downward hole wells and allow forming a borehole charge that is virtually not subject to shrinkage at a height of up to 40 m. Low explosive densities make it possible to effectively use solid column charges for gentle blasting which, in turn, provides a high degree of mechanization of charging operations.

An effective way to rock mass preparation on metallic and nonmetallic quarries Ukraine

A method in experimental studies and industrial-polygon particular conditions justifying the choice of a rational design of an explosive charge. The comparative results of the evaluation of the stress wave’s amplitudes studies and the character of crushing hard media from the explosion of the charge explosives-variable and constant cross section. The dependences of the particle size distribution of various designs explosive charges destroyed by the explosion are constructed. In industrial conditions, the rationale for the explosive boreholes location according to the massif structure. Adjusted boreholes location grid on rational parameters blasting unit, determined using a novel method of breaking rock complex structure. A new design of a combined borehole charge of variable cross section has been proposed. Industrial tests performed and evaluation of the effectiveness of the proposed method blasting locally fractured rocks and ore deposits on non-metallic minerals. Recommendations on their use are given.

Технологические способы ведения взрывных работ, позволяющие безопасно управлять действием взрыва в массиве горных пород

Purpose. The work is devoted to improving the efficiency and safety of the escarpous blasting of rocks by borehole charges of explosives of a new design at iron ore quarries. In the thesis, the features of the process of explosive destruction of rocks by well charges of various designs are investigated. The dependences of their dynamics of explosive destruction on the physicomechanical properties of rocks are established, and the relationship between the distribution of energy of destruction in the medium and the magnitude of the specific impulse of the explosion is determined. Metodology. The obtained regularities of the impulse effect of an explosion associated with the overall energy balance imparted to a destructible medium can serve as a scale for evaluating the effectiveness of the action of well charges exploded simultaneously or through the definition of deceleration. Based on the obtained theoretical and laboratory results, a new design of a downhole charge of explosives with an air cavity in the bottom of the well has been developed. Findings. A feature of this design of the borehole charge is the concentration of the explosion energy in the bottom of the well. The optimal parameters of the air cavity and the location of the initiator relative to it in the technology of blasting have been established. Originality of the work lies in the fact that the conducted industrial tests of a new design of a borehole charge with an air cavity in the bottom part of the well showed its high efficiency. Practical value lies in achieving a reduced specific consumption of explosives. This technological process ensures uniform crushing of the blasted rock mass over the entire height of the ledge and high-quality development of the bottom of the ledge, which opens up real opportunities for the elimination of the re-drilling of the well at the inferior explosive blasting of rocks.

The Change of the Spatial Parameters of the Destruction of the Rock mass by Borehole Charge with Low-Density Tamping

Explosive destruction of the rock formation is substantiated by several theories developed by well-known scientists. The improvement of quality of preparation of rock mass to excavation, by an excavator without an increase in the value of specific consumption of explosives is important in the present time. Traditionally, to increase the impact time of detonation products on the rock hard tamping was used. The problem is in the rational redistribution of the explosion energy due to the use of a borehole charge, and in particular, in the tamping of low-density, porous materials. The more intensive attenuation of the mass velocity of particles in the material of such tamping in comparison with the mass velocity of the rock mass particles contributes to the well channel compression and increases the impact time of detonation products on the rock mass. As a result of redistribution of energy of detonation products, the specific impulse of explosion increases. The value of the radius of the controlled crushing zone increases by more than 1.6 times. The results of industrial explosions in coal mines have confirmed the theoretical reasoning.