Abstract: Focusing on the excavation stability problems of anti-dip rock slope of the west slope of Yanshan Iron Mine, slope inner and slope surface collaborative monitoring network,which consists of borehole inclinometer,anchor stress meter,micro-seismic,high-definition camera,and other means was constructed. Combining field monitoring results with numerical simulation,analysis of anti-dip rock slope deformation mechanism was conducted. The results show that according to the current monitoring,there was only a small displacement change at the depth of 14 m and above,and there is an obvious stress change in the slope affected by rainfall. The high slope section was a potential instability and failure area,and the shallow layer of the slope was easy to form the trend of tension crack and loosening based on the temporal and spatial distribution of micro-seismic events and micro-seismic inversion analysis. Meanwhile,the micro-seismic events showed a dense through distribution,but the possibility of the complete cut sliding along the slope toe was small. The numerical simulation results showed that the deformation failure of the slope was dominated by tensile stress. The tensile crack failure occurred first in the lower step under the cutting action of joints,and the toppling failure occurred in the traction tension in the upper step,which was manifested as toppling and sliding deformation as a whole. The micro-seismic monitoring results were basically consistent with the numerical simulation results,which was a significant reference for on-site landslide early warning and engineering protection.

Key words: anti-dip rock slope,deformation mechanism,field monitoring,numerical simulation