Stability and Distribution of Rock Slope under Asymmetric Excavation

Abstract

The asymmetric excavation unloading activity of a rock slope with a fault has an important influence on the stability of the slope and the division of the surrounding surface influence area. Based on the engineering background of the West Open-Pit Mine in Fushun City, orthogonal testing, K-means clustering, range analysis, and variance analysis were used to study the linkage mechanism of the asymmetric excavation unloading action and the weak structure in the rock slope, as well as their effects on slope stability and the influence area. This analysis showed that the significant factors affecting the stability zones of the north and south slopes were the excavation inclination angles of the opposite slopes. When the excavation inclination of the north slope increased by 10 degrees, the safety factors decreased by 25.9% and 16.6%. When the excavation inclination of the south slope increased by 10 degrees, the safety factors decreased by 13.7% and 1.9%. A second significant factor was the excavation depth. The occurrence of faults in the slope was the main factor affecting the range of slope instability. In order to ensure production safety, the excavation inclination angle of a slope with a fault should be limited to no more than 40°, and the excavation depth of an unstable area with two slopes should be designed to be no more than 450 m. The influence of asymmetric excavation unloading on the stability of a rock slope with a fault structure is expounded. This also provides a theoretical basis for controlling slope stability and influence areas in large-scale open-pit mining projects.

Keywords

• asymmetric excavation and unloading
• rock slope stability
• impact area
• orthogonal test
• K-means clustering