Analysis of coal drawing law and parameter research in shallow buried double hard and extra-thick coal seam

The coal resources in Xinjiang are shallowly buried, the coal seam is thick, resulting in poor top coal caving and drawing. And the roof is overhanging in a large area, which makes it impossible to achieve safe and efficient top coal mining. And at present, there are few related researches on efficient coal drawing in fully mechanized working face of shallow buried double hard and extra thick coal seam. In order to solve the above problems, taking 110501 fully mechanized working face of Yushuling Coal Mine as engineering background, the paper studies the coal drawing law of shallow buried double hard and extra thick coal seam, so as to determine reasonable mining-drawing rate and coal drawing technology, and improve the recovery rate. FLAC3D software is used to analyze the coal and rock failure law in the mining process of fully mechanized working face, so as to design reasonable mining-drawing ratio. The results are listed as follows. ① With the increase of the mining height of the working face, the yield fa