Surface movement and deformation induced by underground mining at Fushun east open-pit mine

In order to investigate the surface movement and deformation induced by underground mining under repetitive mining conditions, the 28002 working face of Fushun east open pit mine was selected as the research object. Based on the actual mining conditions, an underground mining analysis model was constructed using software such as MIDAS and FLAC^3D. By integrating numerical simulation with measured data analysis, this study explored the impacts of repetitive mining in multi-mining areas on the movement and deformation of the overlying rock mass. Specifically, the focus was on the trends of surface settlement and horizontal displacement after repeated mining, as well as the evolution of the range of surface movement and damage caused by repeated mining. The results indicate that as the number of working faces above and below the 28002 face and its neighboring faces increases, the effects of mining-induced deformation interact and superpose, leading to an increase in disturbances to the overlying rock strata and a consequent expansion of the surface deformation and damage zone. Furthermore, the surface subsidence values, horizontal displacement values, and corresponding deformation values obtained from numerical simulations were found to be largely consistent with those from on-site measurements, providing a reliable theoretical basis for the subsequent mining of adjacent working faces.