Deformation and failure regulations of open-pit mine dump caused by underground mining
To study the influence of underground mining on the deformation and failure of the overlying open-pit mine dump slope,the Suancigou Coal Mine and the Harwusu Open-pit Mine dump were taken as the research objects,and the regulations of surface subsidence and the induced failure of open-pit dump were analyzed.The mechanism of deformation and failure was predicted by the probability integral method,and the deformation and surface subsidence of the dump were analyzed with FLAC3D software.And the displacement changes of the open-pit dump after the mining of underground working face were analyzed.The maximum subsidence predicted by the probability integral method is about 21 m,and that calculated by FLAC3D simulation is about 22 m.The maximum surface subsidence of both methods increases firstly and then gradually stabilizes with the progress of the underground mining,and which conforms to the surface subsidence regulation of moving basins.The numerical simulation results are consistent with the actual location of the subsidence area.The horizontal displacement of the dump slope is positively correlated with the advance length of the working face.Along the working face strike,the horizontal displacement maximizes on both sides of the goaf,showing the characteristics of sliding to the middle of the goaf,and generally,the horizontal displacement of the left slope is greater than that of the right slope.
underground mining influenceopen-pit slopedeformation mechanismsurface subsidenceprobability integral methodnumerical simulation