Tomsk Polytechnic University, Tomsk, Russia:

Prokopenko S. A., Doctor of Engineering Sciences, Professor, sibgp@mail.ru

Science Center VostNII, Kemerovo, Russia:
Sementsov V. V., Head of Laboratory of Geomechanics in Mining, Candidate of Engineering Sciences
Dobrovolsky M. S., Senior Researcher
Nifanov E. V., Researcher at Laboratory of Geomechanics in Mining

During room-and-pillar mining, protective pillars of coal are usually left standing. The protective pillars differ in shape, size, process properties and extractability ratios of coal. The authors propose a classification of the protective pillars with respect to their structure and shape in order to estimate and predict their properties. The extractability ratios of coal are calculated for the initial rib pillars and panels at different final shapes of protective pillars. The protective pillars are ranked with respects to the coal extractability ratios. Such systematization of pillars enables selecting the best engineering solutions and innovative improvement of room-and-pillar mining in specific geological conditions toward enhanced safety and efficiency of underground coal production.

The article is prepared in the framework of the Competitiveness Enhancement Program of the Tomsk Polytechnic University.

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