Abstract: The mining depth of acertain polymetallic open-pit mine is large , and the slope is high andsteep. The stability of the mining slope is directly related to the normal operation of the mine, so the analysis and evaluation of its slope stability is crucial. Based on the geological conditions of mining engineering, mining status, and rock mass quality evaluation, a slope model is established for qualitativeand quantitative stability analysis using the technical means of on-site rock mass structure inyestigation+ qualitative analysis of stereographic projection + quantitative calculation of slope limit equilibrium meth-od”. The slope safety coefficients are calculated respectively under three working conditions: selfweight, self weight + blasting and self weight + earthquake. he results show that the current slope ofopen-pit mine is stable as a whole , and meets the requirements of the safety level, which illustrates thatthe slope structure parameters of the stope design have certain rationality. At the same time , it is suggested that smooth blasting and prespliting blasting should be adopted when the slope is close to the slopedesign boundary. lt is necessary to promptly clean up the peeling rocks caused by freeze-thaw action toensure mine production safety and reduce risks.

Key words: open-pit slope, stability analysis;mechanics parameters;limit equilibrium method