Maintaining structural stability is a prerequisite for the safe conservation of archaeological sites. To ensure the structural stability of the sacrificial pits during the excavation process at the Sanxingdui Site, a study was carried out on the influencing factors and protective measures of the sacrificial pits stability. Firstly, a high-precision three-dimensional model was constructed based on the three-dimensional point cloud data of the pit body and the measurement results of the pit top unloading fractures. Subsequently, the Delaunay triangular decomposition method with constraints was employed to establish a three-dimensional grid model incorporating the spatial structure of the fractures. Finally, the horizontal displacement or vibration speed of the pit body under layered excavation, equipment loading, crowd standing, and earthquake action was calculated using the ABAQUS software. Based on the results above, the influence of various conditions and scenarios on the stability of the pit body was analyzed. On this basis, targeted preventive and control measures were adopted to maintain the stability of the pit body. The above research findings indicate that the equipment loading scenario with the long or short side less than 1.5m from the edge, the crowd standing scenario with the long side less than 0.3m or the short side less than 0.2m from the edge, and the earthquake action scenario with a magnitude of VI or above are the most unfavorable conditions for the structural stability control of the pit body. The middle part of the long side of K3, K6+K7, and K8, especially the location of the unloading fractures, is the key object of structural stability control. Therefore, on the one hand, we utilize routine management to implement necessary prevention and control of human-controllable factors such as equipment loading and crowd standing. On the other hand, we employ temporary support structures to cope with natural uncontrollable forces such as earthquakes. Through the combination of proactive prevention and passive control measures, the structural deformation of the pit body has been effectively controlled.

The random distribution of parameter of the surrounding rock have obvious effect on the stability and this paper investigates the influence of the random spatial distribution of rock mass parameters on the stability of surrounding rock. A random field generation method based on the covariance matrix decomposition and GPU acceleration method is proposed. A function that transforms the random field to IMASS constitutive model parameter were successfully established. Afterwards, the effect of the random field under different conditions and the influence on the subsequent simulated excavation were compared. The results show that the random field generated by the Exp correlation function is relatively stable and scattered, and its maximum displacement value varies within a small range; the random field generated by the SExp correlation function is more compact, with a larger fluctuation range of the maximum displacement value, and more dangerous displacements occur occasionally. It can be found from the X, Y correlation length that the distribution of the maximum displacement points is similar. During excavation, the middle, bottom and vault on both sides of the chamber are dangerous areas, and the damage locations are mainly concentrated in the cavern side wall, the junction of the vault and the middle of the side wall.