Abstract
A fully mechanised mining method using continuous miner (CM) for pillar extraction in single-pass is introduced in the year 2010 at Pinoura Mine of South Eastern Coalfields Limited, Bilaspur in India. Overall mining cycle time is reduced by single-pass pillar extraction as it does not require drivage of split galleries in pillars and support installation for such galleries. Further, inherent technical abilities of the deployed CM for faster cutting and quad-bolter for supporting, helped in faster recovery of pillars without creating any strata control issues. Rate of face advance varied between 5–15m/day with an average of 8m/day. Field observations found that CM based single-pass extraction is capable in dealing with the strata control issues during depillaring under weak and laminated (incompetent in nature) roof layers having rock mass rating value around 42. A total of eleven panels, have been depillared under the weak and laminated geology, ranging depth of cover from 59 to 149m in different panels of the mine. During field investigations in these panels, a maximum of 2.89MPa induced vertical stress is recorded and influence of caved roof over underground mining structures is observed up to 15m in the out-bye from the goaf edge. This paper deals with estimation of snook size and limiting roof movement value based on numerical simulation and field studies during the single-pass extraction below the incompetent geological formations.
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Acknowledgements
Authors are obliged to the Director of Council of Scientific and Industrial Research-Central Institute of Mining and Fuel Research (CSIR-CIMFR), Dhanbad and the Director of Indian Institute of Technology (Indian School of Mines), Dhanbad for their permission to publish this paper. Authors are thankful to the colliery management of Pinoura Mine and SMS Limited for their valuable cooperation during the field observation. The views expressed in this paper are those of the authors and do not necessarily reflect the opinion of the institute to which they belong.
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Singh, A.K., Kumar, A., Kumar, D. et al. Field and Simulation Studies for Mechanised Depillaring below Incompetent Geological Formations of an Indian Coal Mine. J Geol Soc India 97, 405–415 (2021). https://doi.org/10.1007/s12594-021-1698-y
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DOI: https://doi.org/10.1007/s12594-021-1698-y