Fissures Distribution Laws of the Underlying Rock Caused by Mining Protective Layer in Shallow Buried Depth

The distribution laws of ground stress shows that the average horizontal ground stress is much larger than the vertical ground stress in shallow depth strata in china, and the horizontal ground stress direction is the direction of the maximum principal stress. According to this, the underlying rock fissures distribution laws in the shallow depth are analyzed; separation fissures are primary, at the same time, a small amount of crossing seam fissures also appear. Finally, the in-site experiments verify the conclusion. In addition, to eliminate the outburst risk about the working face or band area of the protected seams, the work of gas drainage should be done.