Stress Evolution and Roof Breaking Characteristics of Surrounding Rock in Oblique Longwall Mining Area of Steeply Dipping Seam

Taking 3132 steeply dipping coal fully-mechanized oblique longwall mining working face in Lyushuidong Coal Mine as the engineering background, the aricle studies the stress evolution and roof fracture and the spatial scale characteristics of the steeply dipping coal oblique mining area. The results show that the surrounding rock of the steeply dipping coal oblique stope has stress arch characteristics, and the symmetry stress arch along the strike direction is asymmetric stress arch in the decline direction. When the working face is advanced, the main roof stress evolution form is wedge shape→inverted peach shape→inverted trapezoidal and other main forms; the main roof rock layer is tensile and compressive failure in the upper middle part, and the lower part is compressive failure. The peak of the supporting stress of the pseudo stope is slightly larger than the peak of the true inclined stope. As the number of excavation increases, the peak value of the supporting stress gradually increases to produce a cumulative effect. The slope of the pseudo stope is affected by the roof rupture, the “sequence” of the collapse and the “negative constraint effect” of the gangue filling, which is easy to form a large and small asymmetric stope space scale.