Abstract
This study investigates the strata mechanics and convergence monitoring while depillaring in single lift of thick coal seam by cable bolting method. Based on rock mechanical investigations and geotechnical engineering domain, the use of 19-mm-diameter rope as support system and other necessary consumables has been applied to hold the immediate roof over the coal seam. The field application was made in the Bonbahal (R-VI) seam of the case study mine for extraction of full thickness by single lift considering other techno-science parameters. The cable bolting method has success story, while extraction was done by single lift and load haul dumper with belt conveyor combination. The rate of percentage of extraction found 70.12%, and simultaneously no spontaneous heating was observed during extraction of the pillars. Thus, this paper deals with the suitable methods of depillaring to extract thick Indian coal seams followed by scientific observations of immediate roof. Therefore, the research on convergence behaviour of strata will help to design safe extraction of the depillaring panels. Support system and strict vigil of the geotechnical instruments will help to take corrective measures in advance during extraction in safer and efficient manner.
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Acknowledgements
The author of this research paper is extremely gratified to the coal mine operators for data collection, understands the cable bolting methodology and also conveys jovially thanks to the eminent researchers, scientists of the Indian Institute of Technology (Indian School of Mines), Dhanbad, in support of precious counsel, ingenious direction and incessant motivation during the research. The observations articulated inside the research are those of the author and not inevitably of the organization to which he belongs. No organizational funding is involved to complete this research.
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Mangal, A. A Study of Stability Investigation of Immediate Roof for Extraction of Thick Coal Seam in India. J. Inst. Eng. India Ser. D 102, 203–221 (2021). https://doi.org/10.1007/s40033-021-00264-3
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DOI: https://doi.org/10.1007/s40033-021-00264-3