Engineering geology and mechanism of multiple landslides in a large open?pit mine: the case of the Copper Mine in Qinghai Province, China

摘要

Landslides are a commonly occurring hazard in open-pit mines. Despite extensive research on this phenomenon, there is stilla lack of understanding of the mechanism involved in landslides in open-pit mines in certain geologic settings. To reveal themechanisms of multiple landslides in large open-pit mines, the geological engineering conditions in a Copper Mine wereanalyzed in detail. The results were supplemented with on-site investigations, allowing the characteristics of the large-scaleopen-pit landslide events to be summarized. The mechanisms by which geological engineering conditions induced multiplelarge-scale landslides, slope groundwater, freeze–thaw cycles, and blasting vibration were determined. The results show thatfour dominant structural planes are located throughout the serpentinite. The slope rock mass is divided into five engineeringgeological rock groups. The slope failure forms include plane landslides, collapses, and combined failure forms. The areaof the collapsed body becomes gradually closer to the top of the mountain, indicating that the three collapses have certaininheritance and development. Local dangerous rocks at the top of the mountain will eventually slide and are unstable. Thedeformation of the surrounding rock is accelerated, and collapses and landslides are likely to occur in the later stage ofdeformation. The research results provide a reference for the mechanism analysis of similar mine landslide disasters.