-Most of the underground coal mines in the Indian Geo-mining conditions are developed and depillared by Bord and Pillar method. Caving behaviour and strata control are the major concerns to be considered while extraction of coal seams in such workings. This paper describes the results of a scientific strata control monitoring study during depillaring in a contiguous seam working. It includes instrumentation for determining the induced stresses in the pillars and roof-floor convergence in the galleries and junctions with distance from the goaf edges in the working. The mining induced stresses on the pillars were observed to be more in the top seam than that in the bottom seam working. Convergence monitoring was done with Telescopic Convergence Indicators (TCI) and Remote convergence recorders. In general, higher convergence was observed in the junctions as compared to the galleries. The junctions located at distant location suffered more convergence than the galleries is nearer to the goaf edge. Based on the field observation, convergence classification has also been done in terms of average distance of the goaf edge from the point of observation to assess the state of 'No-convergence', 'Initial convergence' and 'Maximum convergence'. The convergence observed in the bottom seam is more than that of the top seam.

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