Cylindrical Caved Space Stability Analysis for Extension Prediction of Mining-Induced Surface Subsidence

Figure 6

The variation of the critical depth of undercut around the cylindrical caved space, above which the surrounding rocks maintain stable from either rock shear failure (i.e., “shear failure”), or the slip failure along discontinuities (i.e., “slip failure due to ” or “slip failure due to ”). The undercut locates at the depth of 168 m (i.e., “undercut depth”), and the slip failure of surrounding rocks along discontinuities will take place at the direction between N18^°W and N55^°W, as well as between S18^°E and S55^°E due to symmetry, because the critical depth of undercut to prevent slip failure due to (i.e., magenta line) locates above the depth of implemented undercut in these ranges of direction.