A safe depillaring design for shallow depth of cover with influence of surface ground movements: a study in Jharia Coalfield
Extraction of coal from a shallow depth of cover especially under multi-seam mining condition requires intensive precautions in respect to safe working and impact on surface structures. A detailed geotechnical investigation is imperative for the design of a suitable support system during depillaring operation. A study has been exercised in Maheshpur colliery of Jharia Coalfield to assess the stability between the parting of VIIIA and VIIIB seams through numerical modeling. The support systems have been framed for split galleries, slices, and goaf edges with the help of well-established Central Mining Research Institute-Indian School of Mines rock mass rating (CMRI-ISM RMR) and NGI-Q system. A suitable method of depillaring has been designed keeping in view the safety of surface structures in respect to subsidence.
KeywordsRMR RQD Rock load Support design Subsidence
The authors thank the Director, CSIR-Central Institute of Mining and Fuel Research, Dhanbad, for permitting to publish the paper. The views expressed in this paper are those of authors and not necessarily of the organization they represent.
The authors received support from the mining industry for facilitating data collection and field studies.
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