Mechanical melioration of geomaterials for making safety cushions in mined-out open kimberlite pits and prediction of temperature–humidity conditions of the cushion in the permafrost zone

The methodology framework is presented for solving specific problems connected with construction of resilient safety cushions at the bottom of open pit mines to ensure further underground mining under the pits by underhand caving systems. It is highly important to perform full-scale studies into physicotechnical properties of geomaterials and mixtures used for making such structures. The paper describes the dedicated and patented experimental setups and the experimentation procedure. The mechanical melioration technology and equipment intended for the safety cushion construction ensure the required grain size composition, looseness and resilience of the cushion during its year-round operation. The mathematical modeling data are discussed, and the features of the mass exchange and heat transfer processes which govern resilience and permeability of the cushion are revealed. The required depression of the cushion is calculated for different values of its thickness. The implementation of the experimental results can allow recommendations on construction of safety cushions with the wanted year-round resilience and permeability and, as a consequence, can enhance safety of underground diamond mining in the permafrost zone.

Kiselev V. V. , Khokholov Yu. A. Mechanical melioration of geomaterials for making safety cushions in mined-out open kimberlite pits and prediction of temperature–humidity conditions of the cushion in the permafrost zone. MIAB. Mining Inf. Anal. Bull. 2021;(12—1):95— 106. [In Russ]. DOI: 10.25018/0236_1493_2021_121_0_95.

Kiselev V. V.¹, Cand. Sci. (Eng.), Senior Researcher;
Khokholov Yu. A.¹, Dr. Sci. (Eng.), Leading researcher, khokholov@igds.ysn.ru;
¹ Chersky Mining Institute of the North, Siberian Branch, Russian Academy of Sciences, Yakutsk, 677980, Russia.

Khokholov Yu. A., khokholov@igds.ysn.ru.

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