In this paper we present results from studies carried out in Indian coal mines with respect to bord and pillar mining and Longwall mining operation. The objective of the study was to know strata-support interaction, assess stability of coal mine workings, identify high stress zone and predict the occurrence of roof falls. The field investigation and analysis of difficult-to-cave roof using powered supports under a massive dolerite sill in central India using a state-of-the-art data logger system are described. A sophisticated PC based data acquisition and analysis system developed at NIRM and installed at Churcha west coal mine to monitor the goaf falls. The system has recorded many roof falls and given clear indication before the occurrence of local and main falls. Multi channel 24 bit digital microseismic monitoring system was installed on the longwall panel P-2 at Rajendra colliery to study the strata behaviour in real time. The result obtained indicated good correlation between microseismic activity rate, roof falls, periodic weighting and propagation of fractures. Among several seismic parameters, microseismic event rate showed a clear indication for short range prediction of impending roof falls in real time. The experience and results from these studies are explained in this paper which could pay the way for successful underground mining in India.
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