Dangerous Zoning and Stability Assessment of Slopes at Antaibao Open Pit Coal Mine in China

Abstract

With the depletion of shallow coal resources in China, the depths and scales of mining have increased. For several coal mines, the extraction has changed from open-pit to underground. Due to open-pit and underground mining disturbance, landslide disasters frequently occur at high and steep slopes of open-pit mines. The effective identification of danger zone of slope and accurate determination of corresponding stability is important in the field of geotechnical engineering. Herein, Antaibao open-pit coal mine was employed as the research object. Firstly, as per the composition and structural characteristics of on-site slope rock mass, six typical disaster factors were summarized, while the assignment criteria for discrete and continuous variables were divided according to the landslide body characteristics and spatiotemporal distribution. Thereafter, based on the comprehensive evaluation principle of fuzzy mathematics, high and steep side stability in the multi-factor influence regions was comprehensively evaluated, while the spatial division of the unstable region was determined. Finally, the slope potential slip surface in the unstable zone of the western side was utilized as the calculation model object, and sensitivity analysis of the slope impact factor was conducted using the MSARMA method. Therefore, the earthquake as well as drainage rate (groundwater dynamics) were determined as the sensitivity factors. The numerical simulation of FLAC3D finite difference method was performed to analyze the evolution law of displacement field under natural, seepage, and vibrational conditions of the northwest slope.