## 3 Numerical Model and Simulation Scheme of the Strain-Structural Plane
### Characteristics of Rockhurst Proneness  
Rockburst proneness is the key basis for studying and evaluating rockburst disasters in the deep rock mass. To distinguish the intensity level and location of rockbursts under different conditions, the structural plane effect on rockburst proneness within the surrounding  
Figure 6: The distribution of fracture information under different conditions (unit: m): (a) \(\theta=30^{\circ}\); (b) \(\theta=45^{\circ}\); (c) \(\theta=60^{\circ}\); (d) \(L=6.5\) m; (e) \(L=8.5\) m; (f) \(L=10.5\) m; (g) \(D=0\) m; (h) \(D=1.7\) m; (i) \(D=3.4\) m.  
rock is further analyzed. Through the secondary development of 3 DEC by FISH language, the distribution of multi-parameter rockburst energy index \(C_{rs}\) of surrounding rock under different conditions is obtained, as shown in Figure 7. To quantitatively analyze the relationship between the parameters of the structural plane and the proneness to rockburst, it is critical to consider that different conditions mainly cause the difference in rockburst proneness between the tunnel and structural plane. Taking the nearest position from the tunnel to the structural plane, the monitoring points A-E are set up in turn along the deep rock mass. The layout of the monitoring points and variation trend of the rockburst index \(C_{rs}\) value of each monitoring point with the structural plane geometric parameters are shown in Figure 8. Combined with Figure 8, the characteristics of rockburst proneness are further analyzed under different conditions. The specific variation laws are as follows. Observing Figure 7a-c, when \(\theta\) = 30\({}^{\circ}\), the \(C_{rs}\) value at the right spandrel is the largest, and an intense rockburst occurs. The rockburst proneness gradually weakens as the rock mass depth increases, the \(C_{rs}\) value decreases to 30. When the structural plane is contacted, the \(C_{rs}\) value is about 35, and a moderate rockburst occurs. When \(\theta\) = 45\({}^{\circ}\), the occurrence range of rockburst decreases, and the \(C_{rs}\) value near the structural plane is 35, which is prone to a moderate rockburst. The \(C_{rs}\) value between the tunnel spandrel and structural plane is basically the same, about 25, which is prone to a weak rockburst. When \(\theta\) = 60\({}^{\circ}\), the distribution of the \(C_{rs}\) value around the tunnel is approximately symmetrical. The maximum \(C_{rs}\) value at the right spandrel is 25, which is prone to a weak rockburst. The rockburst proneness between the spandrel and structural plane reaches the minimum value. The \(C_{rs}\) value is only 17.8, which is not prone to rockburst. The \(C_{rs}\) value increases slightly below the structural plane. Observing Figure 7d-f, when \(L\) = 6.5 m, the \(C_{rs}\) value of the rock mass from the tunnel to the structural plane remains basically unchanged with  
Figure 7: The distribution of rockburst proneness under different conditions: (**a**) \(\theta\) = 30\({}^{\circ}\); (**b**) \(\theta\) = 45\({}^{\circ}\); (**c**) \(\theta\) = 60\({}^{\circ}\); (**d**) \(L\) = 6.5 m; (**e**) \(L\) = 8.5 m; (**f**) \(L\) = 10.5 m; (**g**) \(D\) = 0 m; (**h**) \(D\) = 1.7 m; (**i**) \(D\) = 3.4 m.  
the increasing depth, about 25, which is prone to a weak rockburst. When \(L\) increases to 8.5 m and 10.5 m, the \(C_{rs}\) value near the structural plane increases, and the \(C_{rs}\) value of partly rock mass exceeds 40, which is prone to an intense rockburst. The range of intense rockbursts increases as the structural plane length increases. With the increase in \(L\), the rockburst intensity grade and occurrence range in the risk area gradually increase. Observing Figure 7g-i, the distribution of the rockburst proneness is greatly different from the variation in the distance from the structural plane to the tunnel. When the structural plane intersects with the tunnel, the \(C_{rs}\) values of the vault and the right arch foot are all greater than 40, which is prone to an intense rockburst.