## 3 Highlights and Key Contributions of Published Articles
### Underground Excavation  
In addition to mining engineering, the construction of tunnel projects and underground chambers also involves some complex stability issues.  
[PERSON] et al. (contribution 1) explored the interaction between surrounding rock and support structures during underground cavern excavation to enhance safety and efficiency. It introduces a method for calculating the elastic load coefficient of surrounding rock and a graded release method for plastic load, optimizing the synergy between the initial support and rock. A weighted iterative calculation method for elastic-plastic damage and an evaluation method for the ultimate bearing capacity of surrounding rock are proposed. By monitoring changes in acoustic wave velocity, the study establishes a relationship between wave velocity and rock damage, suggesting a method to determine the optimal timing for initial support installation. Numerical simulations of a diversion tunnel excavation demonstrated the damage evolution of surrounding rock under load release, validating the proposed methods. These findings offer a new approach to quantifying the bearing capacity of surrounding rock and timing support in underground cavern design.  
[PERSON] et al. (contribution 7) examined the causes and distribution of longitudinal cracks in the secondary lining of lower tunnels during the construction of new tunnels above them. Using numerical simulations and on-site monitoring, they found that the construction of the upper tunnel significantly impacts the lower tunnel by altering the stress distribution, leading to cracks. To mitigate these risks, the study suggests chiseling and grouting for areas with fewer cracks and using resin anchor rods with saddle joints in denser areas. It also highlights the need for long-term monitoring and early warning systems for effective crack management.  
[PERSON] et al. (contribution 13) examined the stability of tunnel faces in composite strata, specifically under the condition of a soft upper stratum and a hard lower stratum, which poses significant challenges in tunnel construction. Their research focuses on the Xingye Tunnel project in Zhuhai City, investigating the influence of the soft-hard ratio (SA) on the limit support pressure and failure mechanisms through numerical simulations. A limit equilibrium model was developed based on these simulations, and the results were compared with theoretical models. The study found that tunnel face deformation in composite strata primarily occurs in the soft soil layer, with minimal deformation in the hard rock layer. As SA decreased, there was a linear reduction in the limit support pressure ratio. The tunnel face demonstrated self-stability when SA \(\leq\) 0.125. Among the models analyzed, the truncated log-spiral model (TLSM) showed the closest agreement with the numerical simulation results, particularly for SA values between 0.25 and 1.0, highlighting its effectiveness in predicting limit support pressures under these conditions.  
[PERSON] et al. (contribution 15) proposed an instability model for double-angled trench walls based on 3D sliding body analysis. The objective of this paper was to determine the minimum amount of slurry needed to maintain the integrity of the trench wall. The results show that the center of symmetry on the inside of the wall is the most vulnerable to damage, followed by the inside corner, and then the center and corner on the outside. The consideration of sliding bodies in overall and local stability calculations for double-angled trench wall shapes can provide a reasonable stability assessment.