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At present, studying the parameters of shock waves at pressures up to 20 GPa entails a number of practical difficulties. In order to describe the propagation of shock waves, their initial parameters on the wall of the explosion cavity need to be known. With the determination of initial parameters, pressures in the near zone of the explosion can be calculated, and the choice of explosives can be substantiated. Therefore, developing a method for estimating shock wave parameters on an explosion cavity wall during the refraction of a detonation wave is an important problem in blast mining. This article proposes a method based on the theory of breakdown of an arbitrary discontinuity (the Riemann problem) to determine the shock wave parameters on the wall of the explosion cavity. Two possible variants of detonation wave refraction on the explosion cavity wall are described. This manuscript compares the parameters on the explosion cavity wall when using emulsion explosives with those obtained using cheap granular ANFO explosives. The detonative decomposition of emulsion explosives is also considered, and an equation of state for gaseous explosion products is proposed, which enables the estimation of detonation parameters while accounting for the incompressible volume of molecules (covolume) at the Chapman–Jouguet point.

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The article discusses two deposits of coal mining by the open method. The «Zarechnyi» open-pit is located in Kuzbass, and the «Vostochno-Beiskyi» open-pit is in Khakassia. The main parameters of drilling and blasting operations are given, the geological structure of the deposits is described. The methods of calculating the specific charge, the diameter of the wells and the grid of wells are considered. Blasting operations are an integral part of the mining process. The cost of finished products and the quality of raw materials supplied to the crushing and screening complexes depend on the results of blasting of the rock mass. The currently used retractable blasting technologies, produced according to standard designs, lead to large energy losses during the explosion, as well as to the output of the oversized fraction, which in turn leads to downtime, reduced productivity and breakdown of transport and loading equipment. The paper substantiates the parameters of drilling and blasting operations taking into account the physical processes occurring in the explosive cavity and during the stress wave propagation in the rock mass. Parameters of detonation products are estimated on the basis of shock-wave compression, the refraction of a detonation wave into a rock based on the theory of the breakdown of an arbitrary discontinuity, the stress wave propagation taking into account polymorphic transformations and dissipation energy. Recommendations for reducing the specific charge of explosives, for choosing the diameter of the borehole charge and the grid of wells are proposed.

For the moment, a large number of mining enterprises in Russia engaged in the open-pit mining face with the problem of providing the stability of the directly-embedded concrete poles which are a part of the overall transmission power line system. The blasting operations considered to be an efficient way of developing the deposits strongly affect the concrete poles in the immediate vicinity from the quarries. The major part of electric poles near the deposits has critical deflections from the vertical position. The process of evaluating the stability of the poles affected by the blast-induced ground vibrations should inevitably include the process of determining the criterion of the loss of stability that will help to evaluate the level of the ground vibrations safe for the construction. The paper presents the methodical approach of evaluating the stability to be performed with the help of the finite element model and studies of the stability of a construction having various angles of deflection.