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

Figure 7

The comparison between the prediction by the proposed model and the observation in Google Earth satellite images for the surface subsidence extension in Xiaowanggou iron mine (41.39^°N, 123.63^°E). (a) The circular surface subsidence observed after vertical caving on October 1, 2012. (b) The extended surface subsidence area observed on April 25, 2014. (c) The extended surface subsidence area on May 8, 2017. The blue shadow illustrated indicates direction that the surface subsidence extends to, which is obtained from Figure 6, by comparing the depth of implemented undercut to critical depth of undercut to maintain the surrounding rocks from either rock shear failure or slip failure along the discontinuities.