Analysis on mine pressure bump law of fully-mechanized coal mining face in thin seam with hard roof and hard coal

In order to solve the roof hard control problem of the fully-mechanized coal mining face in the thin seam with a hard roof and hard coal, based on No.8224 fully-mechanized coal mining face in the thin seam of Jinhuagong Mine as the study object, the site monitoring and measuring method was applied to analyze the mine pressure bump law of the coal mining face and the monitoring and analysis were conducted on the working resistances of the powered supports during the coal mining face pushing forward process and the deformation situation of the mining gateway. The results showed that generally the roof weighting would be occurred at the middle of the coal mining face, then the roof weighting would be expanded to the two sidewalls of the coal mining face and the sectional and migrated roof weighting features w ould be occurred. The overburden strata movement above the thin seam would have a lower influence of the coal mining face pushing forward than the medium thick se am. Due to the roof of the coal mining face was hard to control, under the condition of the hard roof and hard coal, an artificial forced roof caving should be taken necess arily and the roof could be effectively caved to ensure the safety mining of the fully-mechanized coal mining face in the seam with the hard roof and hard coal.