NUST MISIS College of Mining, Moscow, Russia:

V. A. Eremenko, Director of Research Center for Applied Geomechanics and Convergent Technologies in Mining, Professor of the Russian Academy of Sciences, Doctor of Engineering Sciences, prof.eremenko@gmail.com
M. A. Kosyreva, Post-Graduate Student
N. G. Vysotin, Senior Lecturer
Ch. V. Khazhy-ylai, Laboratory Assistant at Research Center for Applied Geomechanics and Convergent Technologies in Mining

The key target of room-and-pillar planning for mining rock salt, polymineral salt and polyhalite at the minimized loss of minerals in pillars is optimization of the dimensions of rooms and rib pillars. The authors compare some variants of mining with rooms and rib pillars, as well as with honeycomb mine structure. The theoretical and experimental studies prove efficiency of room-and-pillar dimension optimization by combination of analytical estimation with numerical analysis and physical modeling of the stress–strain behavior of underground structures (honeycomb mine structures). It is found that the honeycomb mine structures feature higher resistability of structural components to external loads. The research into secondary stress field generation and influence on structural elements of the roomand- pillar mining systems made it possible to calculate stable parameters for the conventional and innovative mining systems.
The study was supported by the Russian Science Foundation, Project No. 19-17-00034.

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