# Study on Surface Damage Induced by High Heavy Layer Movement and Mining-Induced Earthquakes
## 3 Results  
### Subsidence Characteristics of Model Without Mining-Induced Earthquakes  
The settlement cloud diagrams of the model without applied seismic stress waves are shown in Figure 9. Specifically, Figure 9a depicts the settlement during excavation from 450-600 m without seismic stress waves, Figure 9b shows the settlement during excavation from 600-650 m, Figure 9c illustrates the settlement during excavation from 650-700 m,  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**No.** & **Frequency (Hz)** & **Energy (J)** & **Maximum Peak Velocity (m/s)** \\ \hline
1 & 5–30 & 296 & 0.13–0.40 \\
2 & 5–30 & 400 & 0.18–0.66 \\
3 & 3–38 & 895 & 0.20–0.65 \\
4 & 3–25 & 1240 & 0.20–0.84 \\
5 & 2–18 & 8270 & 0.34–1.00 \\
6 & 2–18 & 22,600 & 0.79–3.44 \\
7 & 1–15 & 27,100 & 0.44–3.50 \\
8 & 2.5–15 & 50,400 & 0.50–3.27 \\
9 & 0.5–12 & 103,000 & 1.23–3.65 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Frequency range and energy data statistics of mining-induced earthquakes stress wave.  
and Figure 9d displays the settlement during excavation from 700-750 m, all without the application of seismic stress waves.  
As shown in Table 4 and Figure 10, during excavation from 450-600 m, the mining impact was relatively minor, primarily affecting the rock layer beneath the heavy layer. The separation space below the heavy layer was small, and the heavy layer did not exhibit significant bending deformation, the impact on the top stratum was minimal.  
During excavation from 600-650 m, the separation space beneath the heavy layer began to expand, gradually approaching its fracture step distance. The heavy layer underwent bending deformation, causing slight settlement in the top stratum.  
During excavation from 650-700 m, as the heavy layer was further excavated, reaching its fracture step distance, the heavy layer exhibited intense bending deformation. The top stratum experienced increased settlement, reaching the maximum settlement rate during this phase.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Excavation Distance (m)** & **Maximum Top Stratum Subsidence** & **Maximum Heavy Layer Subsidence** \\  & **Displacement (m)** & **Displacement (m)** \\ \hline
450–600 & 0.09916 & 0.31314 \\
600–650 & 0.58410 & 1.13232 \\
650–700 & 5.02025 & 7.95331 \\
700–750 & 5.73751 & 8.14228 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Subsidence displacement of different strata at varying excavation distances.  
Figure 9: Cloud diagrams of the model displacement induced without mining-induced earthquakes: (**a**) excavation of 450–600 m; (**b**) excavation of 600-650 m; (**c**) excavation of 650–700 m; (**d**) excavation of 700–750 m.  
Figure 10: Monitoring data of subsidence induced without mining-induced earthquakes: (**a**) subsidence of top stratum during 600–650 m excavation; (**b**) subsidence of heavy layer during 600–650 m excavation; (**c**) subsidence of top stratum during 650–700 m excavation; (**d**) subsidence of heavy layer during 650–700 m excavation; (**e**) subsidence of top stratum during 700–750 m excavation; (**f**) subsidence of heavy layer during 700–750 m excavation.  
During excavation from 700-750 m, the heavy layer had already undergone significant settlement before this phase, coming into contact with the underlying rock layer. Continued excavation increased the settlement of the heavy layer, leading to further settlement of the top stratum, but at a reduced settlement rate.