Pacific National University, Khabarovsk, Russia

E. B. Shevkun, Leading Researcher, Doctor of Engineering Sciences, Professor, ev.shevkun@yandex.ru
E. A. Shishkin, Candidate of Engineering Sciences, Associate Professor
R. A. Eunap, Senior Lecturer

Industrial mass explosions change the structure of rock mass both directly in the fracture zone, due to the opening of closed cracks, and in the pre-fracture zone at a considerable distance, where new cracks are generated and prerequisites for incipient cracks arise. Ignoring these changes when carrying out blasting operations near slope structures often leads to a breakdown of their stability and to the initiation of landslides, up to catastrophic. It is known that in mass blasting of the order of a hundred tons of explosives, the width of the residual deformation zone reaches 40–50 m. In most cases, pitwall is protected from the effects of mass explosions by implementation of wall control blasting before a mass explosion. The article proposes a new technology for conducting massive explosions with borehole blasting along the working front and with the start of the explosion from the pitwall toward the slope, with the constant deep confinement of blasthole rows by intact rock mass. The main advantage of the proposed technology is the threefold reduction in the impact of stress waves in the direction of the pitwall rock mass. Ten years of experience in using this technology has made it possible to form a stable pitwall at its ultimate limit without additional cutback measures.
The study was supported by the Russian Science Foundation, Grant No. 24-27-20036, https://rscf.ru/project/24-27-20036/, and by the Ministry of Science and Education of the Khabarovsk Krai. The authors express their gratitude to Amur Minerals LLC for the granted possibility to implement instrumental measurement of change in rock mass damage indicators nearby blasting blocks at different parameters of mass blasting.

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