## 4 Analysis of Physical Similarity Simulation Experiment Results
### Distribution Law of Abutment Pressure (AP)  
Figure 7 illustrates the AP curve of the working face during mining in the first and second mining strips. When the working face advanced to 34 m, stress release occurred in the mined area of the stop, and abutment pressures on both sides of the coal wall reached 4.85 MPa and 4.62 MPa, respectively, which is 1.68 times the original rock stress. The area 15 m ahead of the working face was affected by the advance abutment pressure. When the working face advanced to 49 m, the AP reached 6.34 MPa, which is 2.2 times the original rock stress, and the area 20 m ahead of the working face was affected by the advance abutment pressure. When the working face advanced to 63 m, the abutment pressure on the goat roof reached 5.85 MPa, which is 2.1 times the original rock stress, and the area 20 m ahead of the working face was affected by advance abutment pressure. When the working face advanced to 77 m, the AP reached 5.96 MPa, which is 2.1 times the original rock stress, and the area 20 m ahead of the working face was affected by advance abutment pressure. When the working face advanced to 92 m, the abutment pressure reached 6.35 MPa, which is 2.2 times the original rock stress, and the area 20 m ahead of the working face was affected by advance abutment pressure. When the working face reached 106 m, it was 27 m below the second mining strip, with an AP of 5.95 MPa, and the area 20 m ahead of the working face was affected by advance AP.  
As depicted in Figure 8, when the working face advanced to 121 m, it was 5 m away from the ICP, and the AP was 5.83 MPa. When the working face advanced to 135 m, it was 8 m below the ICP. The main roof strata slipped and became a failure behind the support, while the fissure developed upwards and penetrated the ICP. The upper IRS rotated towards the goat, resulting in a rise in AP to 7.98 MPa. At this point, the concentrated load on the OR of the ICP caused a cutting failure in the IRS from top to bottom, exerting a dynamic pressure on the working face of the lower coal seam. The cutting failure of the IRS caused transient instability in the double-arch bridge structure on the right side of the ICP. The sudden release of concentrated load from the OR further accelerated the fracture of the IRS, resulting in a more severe dynamic load impact on the working face. Consequently, the AP reached 9.85 MPa, with the area 25 m ahead affected by advance support pressure. The working face continued to advance to 165 m, and it was located below the third mining strip, with the AP reaching 7.65 MPa and the area 20 m ahead being affected by advance AP.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{1}{c}{**Number of Weighting**} & **Advancing Distance/m** & **Weighting Interval/m** & \begin{tabular}{c} **\(P_{\text{aver}}\)** \\ **(KN)** \\ \end{tabular} & \begin{tabular}{c} **\(P_{\text{main}}\)** \\ **(KN)** \\ \end{tabular} & \
\begin{tabular}{c} **Dynamic Load** \\ **Factor (\(q\))** \\ \end{tabular} \\ \hline \multirow{10}{*}{
\begin{tabular}{c} **Figure 9 shows the changes in abutment pressure as the working face passed through the third and fourth mining strips. The variation in surrounding rock pressure during this stage was similar to that observed in the first and second mining strips. The surrounding rock pressure ranged from 5.93 to 6.3 MPa. After the working face was out of the 2# failed TCP, the abutment pressure reached 6.7 MPa, indicating an increased surrounding rock pressure compared to that of the support in the mining strip of the stope.