ЕНЕРГЕТИЧНІ ВТРАТИ ВИБУХУ СВЕРДЛОВИННИХ ЗАРЯДІВ В УМОВАХ ГІРСЬКИХ СХИЛІВ

Abstract

In article considers the peculiarities of designing the parameters of mass explosions in the conditions of development of mineral deposits on mountain slopes. In these conditions, the width of the working platforms, the height of the ledges and, accordingly, the length of the well charges is limited by the slope. Particular attention is paid to the initial stage of formation of the mechanical effect of the explosion in the marginal areas of the elongated charge. The specifics of the choice of technological parameters of a mass explosion in mountain conditions are studied, where due to a significant difference in height within one block the height of the ledge can vary within 5 ... 10 m, and the charge length can reach 2… 7 meters. Due to the reduction of the length of the downhole charge, the participation of its end parts becomes more significant, where up to 35 ... 40% are dissipative energy losses due to the change of the symmetry of the force field. The studies take into account the peculiarities of the manifestation and development of edge effects at the ends of the charge. Regularities of stress field formation taking into account boundary phenomena have been studied by analytical calculations based on the replacement of a linear charge by a system of concentrated charges. Based on the compiled algorithm, the parameters of the force field for different variants of instantaneous and delayed explosion of a system of concentrated charges are calculated. Calculations of boundary phenomena in the explosion of a well charge of limited size show that under the condition of instantaneous charge initiation simultaneously on both ends of the charge, the degeneration of the axial symmetry of the force field occurs from the ends of the charge to a depth of 50 radii. The results of the calculations indicate that in real conditions of detonation of short downhole charges, their mechanical effect is largely formed by the weakened end sections of the linear charge. Analysis of the results of calculations allows us to recommend rational parameters of the system of downhole charges, which minimize energy losses