Research on Strata Behavior Characteristics of Nearly Shallow-buried Coal Seam with Large Mining Height

In order to master the law of strata pressure behavior of large mining height working face in nearly shallow buried coal seam of Yushen Coal Mining Area, N1200 fully mechanized longwall mining face in the mining area is chosen as the research object, and physical model experiment of similar material is carried out. The results show that the initial working pressure of N1200 face is 56 m, the average step pressure is 15.8 m, the working resistance is 4 843 kN, the dynamic load factor is 1.95, and the resistance of support reaches 9 739 kN. Due to the influence of double-critical laminated damage, the working face presents large and small periodic pressure phenomenon. When the pressure is in small cycle, the collapse angle of rock is mainly distributed on the main key stratum. When the pressure is in big cycle, the coefficient and the peak value of the advancing bearing pressure are increased.