Abstract: Open pit blasting mining or slope blasting forming may cause varying degrees of damage to the slope rock mass,and coupled with water seepage,it will seriously threaten the stability of the slope. To investigate the relationship between rock damage and slope stability of the eastern slope of Yanshan Iron Mine,a series of uniaxial compression and acoustic emission monitoring experiments were conducted on saturated biotite granulites with different initial damage degrees. The crack propagation characteristics of saturated biotite granulites with different initial damage degrees were studied. The experimental results show that as the initial damage degree increases,the deformation degree of the microcrack compaction stage of saturated biotite granulite increases,and the elastic modulus shows a decreasing trend. The average values of cracking stress,damage stress,and uniaxial compressive strength are quadratic functions of the initial damage degree,and all three decrease with increasing initial damage degree. The initial damage degree increased from 0 mV to 50 mV,60 mV,and then to 70 mV. In the stable expansion stage of microcracks in saturated biotite,the expansion angle first increased from 0. 28° to 0. 9° and then decreased to 0. 34°,and in the unstable expansion stage,the expansion angle increased from 5. 98° to 7. 73° and then decreased to 7. 69°. Microcracks developed from full expansion to incomplete expansion,and their failure mode transitioned from single shear failure to a combination of shear and splitting,resulting in more severe rock failure. The experimental results can provide theoretical reference for the safe maintenance of rock mass on open-pit mine slopes. 

Key words: slope stability,biotite leptynite,uniaxial compression,initial damage,microcrack