| Fushun West Open-pit Mine located in Fushun City,Liaoning province has become the largest deep-pit open pit in Asia due to its perennial mining.While providing a source of economic construction for Fushun City,a series of geological disasters are accompanying.So far,the Fushun West Open-pit Mine has experienced relatively rare large-scale sliding geological disasters in both the northern and southern gangs.Moreover,for urban areas near mining areas,problems such as surface subsidence,ground fissures,structural cracks,and foundation overturning are not uncommon.Therefore,mine earthquakes caused by the internal stress release of the formation caused by excessive mining also occur from time to time.At present,experts and scholars have conducted in-depth research on the static stability of the north and south sides of the West Open-pit Mine,and the governance work is relatively mature.However,with the deepening of mining and moving eastward,the problem of geological disasters near the east side of Fushun West Open-pit Mine is also increasing day by day.The East Bang will also become the focus of the next research and governance work.Moreover,Fushun City is located above the Tanlu earthquake zone,and there is a potential risk of earthquakes at any time,and mine earthquakes occur frequently.Although the West Open-pit Mine is relatively stable as a whole,when an earthquake occurs,a serious of disasters may occur,which will seriously threaten the development of cities near the mining area and the lives of the people.Therefore,it is particularly important to study the stability of the West Open-pit Mine under dynamic conditions.This article focuses on the analysis of the east side and near area of Fushun West Open-pit Mine,using FLAC3 D software,aiming at clarifying its potential static and dynamic response characteristics and influencing factors as well as failure modes under seismic loading and obtaining its safety margin and safety evaluation information,etc.The main contents in the dissertation are as follows:(1)The research progress of slope stability at home and abroad,and potential geotechnical disasters and existing key problems of Fushun West Open-pit Mine is summarized.The instability failure of the slope and its judgment method are introduced in detail.The strength reduction method to solve the safety factor method is also described.(2)Based on the specific geological and geomorphic features,a relatively precise plain finite element analysis(FEA)model for the pit is established,laying a foundation for the analysis of potential geotechnical disasters.Based on the geometrical and physical features of the pit,etc.,the pre-processing of simulation analysis is focally introduced and an FEA model is established by selecting the reasonable modelling and analysis method.The effectiveness of the established FEA model is validated by comparing the numerical results with a model test one.(3)The static and dynamic stability of the east side of West Open-pit Mine is analyzed,respectively,clarifying the potential forming mechanism of geotechnical disasters and main influencing factors.The riskiest sliding surface under the critical failure state is determined through the static and dynamic stability analysis,and hereby investigating the displacement movement situation of the sliding block under the critical sliding failure of the slope.The dynamic response and its basic law of the slope of the east side is analyzed.The potential disaster forming mechanism and the basic law is explained through the analysis.(4)Based on the static and dynamic analysis,the safety margin is determined,and the safety evaluation is performed.Hereby,the safety coefficient and failure mode of the east side and its near zone of the slope are calculated under the critical failure state for determining the safety zone by using the safety coefficient method.Based on the dynamic analysis results,the safety evaluation is performed to estimate the stability of the slope under different seismic responses. |
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