## 4 Simulation Analysis of Mining Failure Effect of Through-Type Fault Floor  
### Numerical Model Construction  
Based on the theory of fluid-solid coupling, a numerical calculation model for water inrush from through-type faults in the 112,124 excavation face of the Xin'an Mine is established using FLAC\({}^{3\text{D}}\). As shown in Figure 9, the model size is 1300 m \(\times\) 240 m \(\times\) 480 m (Length \(\times\) Width \(\times\) Height), with a total of 24,468 cells and 30,100 nodes. The working face is the mining 2 # large coal seam, with a thickness of 4.5 m and an average dip angle of 15\({}^{\circ}\). The working face has a strike length of 85 m and a dip length of 110-125 m. There are three faults, F\({}_{3}\), F\({}_{38-1}\), and F\({}_{55-1}\), with inclinations of 60\({}^{\circ}\), 60\({}^{\circ}\), and 75\({}^{\circ}\), and a width of 30 m. Among them, the F\({}_{55-1}\) fault has a strike of 59\({}^{\circ}\) and a drop of 120 m. Taking the advancing direction of the working face as the X direction, and the inclination direction of the working face as the Y direction, 60 m and 100 m are reserved on both sides to offset the boundary effect. Rock mechanics parameters are shown in Table 7. In order to study the synergetic water inrush caused by the damage and fracture of the coal seam floor and the seepage and uplift of the confined water in the through-type fault zone during the advancing process of the working face, monitoring points are mainly arranged in the coal seam floor and the F\({}_{55-1}\) through-type fault zone. A1-\(\sim\)A4-9 monitor the seepage change law of the surrounding rock displacement field and stress field. B1-1-B1-60 are the pore water pressure monitoring points to monitor the seepage flow field and water pressure change law in the F\({}_{55-1}\) fault zone. The layout of monitoring points is shown in Figure 10.  
Collaborative Water Intrusion Process of Complete Rock Layer Rupture and Progressive Intrusion of Fault in the Bottom Plate  
During the process of selecting coal seam mining, the progressive intrusion development of the intact rock layer zone and the plastic zone of the fault zone in the floor under different distances of advancing the working face should be analyzed. As shown in Figure 11, as the working face advances, the goaf changes the stress equilibrium state of the model, and the plastic failure zone shows an increasing trend. The plastic failure zone of the intact rock layer on the floor is continuously approaching the seepage area around the F\({}_{\text{55-1}}\) fault until it connects. The front end of the work face and the interior of the F\({}_{\text{55-1}}\) fault zone are mainly subjected to shear failure, while the top and bottom of the goaf are mainly subjected to tensile failure. When the working face advances 75 m, the intact rock layer zone of the floor and the F\({}_{\text{55-1}}\) fault zone undergo shear failure, and there is a plastic failure depth of 12 m below the right side of the goaf. When the working face is advanced by 250 m, the plastic failure depth of the intact rock layer on the bottom plate reaches a peak of 30 m. When the working face is advanced by 475 m, the stress at the front of the face affects the F\({}_{\text{38-1}}\) fault, causing  
Figure 11: Cloud Chart of the Progressive Plastic Distribution of F\({}_{\text{55-1}}\) Fault and the Rupture of Surrounding Rock in the Bottom Plate. (**a**) Working face advancing 75 m, (**b**) working face advancing 250 m, (**c**) working face advancing 475 m, (**d**) working face advancing 500 m, (**e**) working face advancing 525 m, (**f**) working face advancing 625 m.  
Figure 10: Model Monitoring Point Layout. shear failure inside, and the F\({}_{\text{55-1}}\) fault begins to ascend vertically. When the working face is advanced by 500 m, the F\({}_{\text{55-1}}\) fault vertically advances to the floor of the 2 # coal seam, but the pressure bearing water conducting zone inside the fault is not fully connected.