Study on the failure pattern of mining-induced landslides based on discrete elements

Abstract

Mining-induced landslides are a common form of disaster in the mountainous areas of coal mines. To clarify the deformation and failure patterns of such slopes under the mining action, the particle discrete element method was employed to simulate the destabilization damage process of the anticline coal seam slope under two conditions, single-seam mining and three-seam mining, and analyze the characteristics of crack expansion and rock fragmentation during slope deformation, based on the field investigation of typical mining-controlled landslides. The results show that: 1) In a single-seam condition, an arch-ring type deformation zone is created in the roof area after the coal seam is excavated and evolves into a fallen rock body; while the rock body at the interval of multi-layer excavation will be bent sink collapse, forming a large area of rock fragmentation. 2) Under different excavation conditions, the internal crack evolution and rock fragmentation of the slope are slow at the beginning of the formation of the fall zone and stress redistribution. The stage of roof emergence and rock bending fracture is the main stage of rock fracture and fragmentation. 3) The anti-inclined coal seam mining-controlled mountain failure pattern is mainly manifested as follows: Coal seam mining →Arch-loop-like fall of the roof →Bending and sinking of the internal rock →Pulling and breaking of the trailing edge →Failure of the locking zone at the foot of the slope → Shallow sliding of the fragmented rock. This study provides a new direction for the analysis of the destabilization mechanism of mining-controlled slopes and scientific guidance for the prevention and control of landslide hazards in mining areas.

Keywords

• mining-induced
• collapse and landslide
• rock fragmentation
• failure pattern
• discrete element method