Design of rhombus coal pillars and support for Roadway Stability and mechanizing loading of face coal using SDLs in a steeply inclined thin coal seam—a technical feasibility study

  • Mohammad Jawed
  • Rabindra Kumar SinhaEmail author
Original Paper


Coal seams that dip more than 15° are classified as steeply inclined in Indian mining context. Mining of steeply inclined seams poses variety of problems starting from strata control to problems related to efficient mechanisation. Sawang-C seam of Govindpur Underground Project of Central Coalfields Limited is one such seam. Presently, the seam is being developed on bord and pillar method of mining, and the blasted coal is loaded manually into tubs using hand shovel and basket. In order to mechanise the loading operation, technical feasibility of formation of rhombus pillars and deployment of side discharge loader (SDL) are investigated along with design of supports from the point of view of roadway stability. This paper thus seeks to address the technical feasibility of deployment of Side Discharge Loader in a 1.7–2.2-m thin seam inclined at 16° if developed with rhombus pillars and to suggest suitable and adequate support system for such workings.


Bord and pillar mining Steeply inclined seams Rhombus pillars Thin seams Numerical modelling 



The authors are thankful to the participants of the Consultancy Project (CONS/3116/2015-16) titled ‘Design of rhombus coal pillars and support with roadway stability of Sawang-C seam of Govindpur underground project sponsored by Central Coalfields Limited, a Subsidiary of Coal India Limited. The views expressed in this paper are those of the authors, and not necessarily of the institute which they belong to. The authors also acknowledge the contributions of Mr. Aditya Mishra and Mr. Vijay Shekar, Scientist, NIRM, Bengaluru, India for some of the numerical modelling analysis.


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Copyright information

© Saudi Society for Geosciences 2018

Authors and Affiliations

  1. 1.Indian Institute of Technology (Indian School of Mines)DhanbadIndia

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