Study on Temporal and Spatial Characteristics of Overlying Strata in the Deep Coal Mining Process

This study adopts the stress relief method to test in situ field obtain distribution characteristics of no. 2 + 3# coal seam. A three-dimensional model was established with S3012 working face as engineering background, and measured values were applied model, spatial-temporal evolution rock mass around stope during seam mining studied. The specific conclusions are follows: map front of, behind, on both sides process obtained. As goes on, maximum value supporting formed shifts corner, presenting a “hump-like” distribution. concentration coefficient front, back, increases linearly increase size. Under same size, is smallest, largest. displacement nephogram overlying strata With continuous advance face, roof undergo dynamic subsidence process, continuously, showing shape “bowl” sharp bottom. In mining, showed an “O” characteristic. cloud plastic zone obtained, failure volume gradually progress face.