Influence of Mine Earthquake Disturbance on the Principal Stress of the Main Roadway near the Goaf and Its Prevention and Control Measures

Figure 7

Evolution track of principal stress direction under dynamic load disturbance. (a) Before dynamic load disturbance; (b) dynamic load disturbance 0.01 s; (c) dynamic load disturbance 0.03 s; (d) dynamic load disturbance 0.05 s; (e) dynamic load disturbance 0.07 s; (f) dynamic load disturbance 0.09 s.