Abstract: Aiming at the traditional analysis of open pit slope stability under condition of concealed single gap could not reflected rock damage state quantitatively and intuitively, influences of 5 different position concealed single gap below a open-pit slope to slope stability were simulated and analyzed by using Mohr circle. The research indicated, roof of concealed single gap of open pit slope was the weakest area in gap, slope was much stable with the distance much longer between concealed single gap to slope.

Key words: Open pit slope, Concealed single gap, Mohr circle, Stability