## 1 Introduction  
With the increase in mining depth, engineering disasters are increasing, such as mine rock bursts, roof falls, intensified mine pressures, large deformations and the rheology of surrounding rock, and high ground temperatures, which pose a great threat to the safe and efficient mining of deep resources [1]. The problem of rock mechanics in the process of deep resource mining has become the focus of research worldwide [2; 3; 4; 5; 6; 7]. Deep rock mass is under high induced stress, and it is difficult to predict what kind of failure will occur. Under high induced stress, even high-quality rock can fail due to instability. Therefore, when designing and controlling the stability of deep mining projects, it is necessary to fully consider what kind of failure the rock will exhibit under high-stress conditions. Deep rock mass failure can be classified as structure-controlled failure and stress-induced failure based on the structural characteristics and stress characteristics of the rock mass and the size of the surrounding rock failure. Structure-controlled failure manifests primarily as rock block fall and wedge instability. There are discontinuities in the rock mass, including layers and joints, or large-scale discontinuities, including faults, shear zones, etc., which form structural weak zones in the rock mass. The existence of weak structural surfaces makes it possible for the drift surrounding the rock to collapse during excavation. Stress-induced failure is mainly expressed as spalling, rock bursts, and squeezing deformation of surrounding rock. Before drift excavation, the rock mass is in the state of stress equilibrium. After excavation, there are stress concentrations in the surrounding rock drifts. If the stress level is greater than the strength of the rock mass, the rock mass will yield or fail, producingcracks and spalling on the excavation surface, a high-strength rock body, and even rock burst [8]. Controlling the stability of the surrounding rock requires a thorough understanding of the rock mass's properties. It is the foundation for preventing and controlling these failures to maintain project stability by studying the geological characteristics of complex engineering rock masses and obtaining the mechanical properties of engineering rock masses to select appropriate support measures [9; 10; 11; 12; 13; 14]. The anisotropy of engineering rock mass is significant due to its complex structure and the random distribution of joints and cracks in it, due to which the failure mechanism differs greatly [15; 16; 17; 18]. To maintain the stability and safety of engineering rock mass, it is essential to accurately understand the physical and mechanical properties of the engineering rock mass [19; 20; 21]. The mechanical parameters of rock mass are affected by many complex factors, such as the mechanical properties of rock block, spatial morphology and mechanical properties of the structural plane, excavation disturbance, and in situ stress. The classification method of engineering rock mass is a comprehensive index based on the combination of the above factors; thus, it has some inherent correlation with the mechanical parameters of rock mass [22]. In situ test methods and assumption-based inversion analytical methods to determine rock mass mechanical parameters are time-consuming and expensive. The classification method not only provides simplicity and efficiency in obtaining rock mass mechanical parameters but also allows designers to make timely decisions in the field if there are sudden changes in rock mass conditions. Therefore, after establishing the empirical relationship between engineering rock mass classification index and rock mass mechanical parameters based on the measured data, it is undoubtedly a more practical method to estimate the mechanical parameters of rock mass [23; 24; 25].