### The Evolution Law of the Influence of Mining Area Location on Fault Activation
#### 2.1.2 Analysis of the Stress Change of Fault Plane Caused by Mining  
Figures 6 and 7 show the normal stress and shearing stress distribution on the plane of the fault at different distances to the fault hanging wall within the mine area, respectively. As can be seen, the additional shearing stress and normal stress are produced on the fault plane due to the effect of mining, which changes both normal stress and shearing stress. The shear stress to normal stress ratio is greater, the fault is activated more easily. This is due to the possible increase in shear stress and decrease in normal stress under the influence of mining, resulting in shearing stress surpassing the shear strength. Figure 5: Line chart of horizontal displacement distribution of surrounding rock on monitoring line at different distances from the mining area to the fault, they should be listed as: (**a**) The mining area is located in the fault hanging wall; (**b**) The mining area is located in the fault footwall. Figure 6: When the mining area is situated within the fault hanging wall, the shear stress distribution on the fault plane is at various locations. The major features of shearing stress distribution when excavating fault hanging walls are listed below. 1 Within the depth of 0 to \(-400\) m, the additional shear stress is positive. the shearing stress reduces in parallel with the increment of the mining zone distance to the fault, making it less likely that the fault will be activated. The additional shear stress reaches its maximum at a depth of \(-70\) m. For example, the largest value of additional shear stress is 0.259 MPa at 30 m from the mining region to the fault hanging wall which decreases linearly downward. The normal tensile stress increases significantly again until the extrusion area appears. This is consistent with the reason that excavation causes the shallow opening and sliding of fault hanging wall and the center of gravity downward enhances the compression of the lower unpulled fault plane; 2 In the depth range of \(-400\) m to \(-700\) m, the shearing stress on the fault plane increasingly differs from the shearing stress at initial equilibrium as the distance between the excavation area and the fault decreases. The additional shearing stress is negative. The progressive reduction in shear stress may contribute to the progressive decline in the probability of fault activation. The Coulomb-Mohr criterion [53] and the Byerlee fault slip criterion [54] both state that the fault has not undergone activation dislocation within this depth range. The normal stress distribution exhibits the following primary characteristics during the excavation of the hanging wall of the fault. 1 Between 0 m and \(-300\) m in depth. Additional tensile stresses are essentially absent when the fault plane is more than 90 m from the mining zone. but when it is less than 60 m, a slight increase in normal stress; 2 Between \(-300\) m and \(-700\) m in depth. The additional tensile stress is negative, as well as decreasing with the distances between the excavated area and the fault, the maximum value of additional tensile stress tends to move to the bottom left of the goaf. The reason being that the vertical distance from the lower left of the goaf to the fault is nearest, and after excavation and unloading, there is significant additional tensile stress in the fault plane. Figures 8 and 9 depict the normal stress and shearing stress distribution on the fault plane for various distances from the mining area. It can be seen that the main characteristics of the shearing and the normal stress distribution are as follows. 1 Additional shear stress is negative in the depth range from 0 to \(-100\) m. When the fault plane is farther away from the extraction area, the shearing stress reduces and the normal stress rises on the fault plane; 2 the additional shear stress is negative between \(-100\) and \(-400\) m deep.