Geo-technical investigations in the first continuous miner area of The Singareni Collieries Co. Ltd.

摘要

In the Singareni Collieries Company Limited, Venkatesh Khani-7 shaft mine is situated in the South Central part of Kothagudem coalbelt. In this block, queen seam, king seam, and bottom seams are under exploitation. The king seam is being worked in two sections viz top and bottom sections. In the king seam (top section), it is proposed to introduce continuous miner for the first time in the company. To ascertain the roof strata behaviour geotechnical investigations comprising micro logging of core samples, underground mapping to trace the cleat pattern, discontinuities viz. joints, slips, fractures etc, geo-engineering properties of roof strata, rock quality designation (RQD), rock mass rating (RMR) and caving index were taken up. The underground mapping has helped to infer most prominent joints, most prominent slips, face cleat and butt cleat trends, the tension fractures due to longwall panels (goaf) in the overlying queen seam etc. Compressive strength of the roof strata ranges from 79 to 253 kg/cm~2. RQD ranges from 38 to 100 percent classifying the strata as "poor" to "very good". RMR of the roof strata varies from 41 to 53 indicating the roof strata is "fair". Range of caving index of the roof strata is 133 to 3767 indicates "weak roof" to "roof cavable with difficulty". Thus these studies have helped to a large extent to assess the roof strata behaviour.