Analysis on Mine Pressure Behavior Law of High Cutting Coal Mining Face in Seam with Thick Overburden Base Rock and Shallow Mining Depth

In order to master the mine pressure behavior law of the high cutting coal mining face in the seam with a thick overburden base rock and a shallow mining depth,taking the No.61203 coal mining face in Wulanmulun Mine as the prototype,with the similar simulation experiment,the mine pressure behavior law of the high cutting coal mining face with the thick overburden base rock and shallow was obtained.The roof initial weighing distance between two step of the coal mining face was 42 m and the roof periodical weighing could be divided to a long periodical roof weighing and a short periodical roof weighing.When the initial roof weighing came,a part of the stratum in the thick key stratum would be collapsed.The short periodical weighing generally would be a part of the thick key stratum involved.The long periodical roof weighing would have the above stratum involved.In the overburden strata above the coal mining face,there would be the three zones divided similar as under the conventional mining conditions.The operation of the powered support in the coal mining face was not stable,the max work resistance of the powered support was 9 882 kN,which was 1.15 times of the rated work resistance.The study showed that the present available support could not meet the requirements and it proposed to select the powered support with a higher work resistance.