Study On Slope Stability And Repair Scheme Of Back Hill Quarry In Hancheng,Shaanxi Province

Hancheng is the only county-level city in Shaanxi that has won the title of“China's Excellent Tourism City”.It is the east gate of Shaanxi and the northeast gateway of Guanzhong City Group.Its urban ecological landscape is related to the overall image of Shaanxi Province and Guanzhong City Group.In the early days,the mining industry and the mineral processing industry in Hancheng had made great contributions to regional economic and social development,but the current problems and contradictions are also very prominent.Based on the project of“Ecological Restoration and Agricultural Reconstruction of Coal Mining Subsidence Area in Hancheng City”,this paper takes the slope stability and ecological restoration of the abandoned quarry area in the southwestern part of Shangyukou Village of Hancheng City as the research direction,through detailed on-site investigation and cataloging,combined with previous survey data,evaluate the soil erosion after excavation,the stability of engineering slopes and abandoned slag bodies,and analyze various geological environmental problems caused by quarrying.,and on this basis,combine local climate and suitable growth plant screening,Ecological environment restoration program.This article mainly achieves the following basic understanding:?1?The study area is located on the north side of the Hancheng Great Fault?F₁?,and the southeast belongs to the Loess Plateau area.The terrain is flat and the southwest is a wrecked hilly area.The terrain is undulating and the Cambrian system is mainly exposed.In the stratum,the pre-harvest vegetation is rich and the coverage is high.After the quarrying,the slope is bare and irregular,the vegetation is seriously damaged,the rainfall in the area is large,and the soil erosion is serious.?2?Through the investigation and analysis of the structural surface of the study area,except for the slope of the Baojia quarry project,the slope is the forward slope,and the rest is the reverse slope.The slope is composed of medium-thick limestone and muddy rock.weathering.Based on the investigation of slope deformation of field engineering,it reveals three kinds of deformation failure modes:dumping failure,plane slip-pull failure and wedge-shaped body failure.On the other hand,through detailed investigation of the abandoned slag body in the study area,the distribution is known.Basic characteristics such as composition,shape and scale,combined with remote sensing interpretation of UAV 3D imagery,the waste slag body is divided into platform type spoil body,slope type spoil ground,channel type earth and stone mixed discard according to material composition and accumulation position.There are four types of slag body and sloping earth-rock mixed waste slag body.On this basis,the possible instability methods of each slag body,including circular landslide and collapse,are analyzed.?3?Based on the red plane projection method,the boundary conditions of potential deformation and instability of rock slope are studied.The stability of slope under structural plane control is analyzed.The control structure surface which affects the stability of slope is determined,and then the strength is used.The reduction method establishes the model,sets the boundary conditions,selects the reasonable physical parameters,and numerically simulates the rock slope,analyzes the stress,displacement increment,plastic zone and maximum shear strain increment,and finally determines the overall slope.stability.After that,using the simplified Bishop method to analyze the stability of the main waste slag in the study area,consider the natural and saturated conditions,calculate the most dangerous sliding surface of the slag body slope and its stability coefficient,and view the waste slag body.When the contact surface with the natural slope is the sliding surface,the steady state of the slag body is evaluated,and the influence of rainfall on the slope stability is evaluated.?4?Statistics on the exposed area of the slope,the area of the pit and the amount of waste slag in the study area,and investigate and analyze the main geological environmental problems in the study area,including geological hazards?collapse,landslide,debris flow?,visual pollution(Exposed rock slopes and pits are analyzed for environmental effects that restrict human activities?occupying land resources,non-safe areas,dust pollution?,according to the characteristics of engineering slopes,pits and abandoned slags,and the existing geological environment.The problem raises the goal of engineering governance.?5?Using the combination of engineering scheme and biological scheme to carry out ecological restoration of abandoned quarry.Firstly,two engineering treatment schemes for slope filling and rock wall drilling are proposed for high-steep rock slope,aiming at waste slag.The system proposes two kinds of treatment schemes:gentle slope type and flat type.At the same time,according to different engineering management schemes,corresponding support schemes are proposed.On this basis,vegetation restoration is carried out,and the most suitable plants are screened by analytic hierarchy process.The species includes trees,shrubs,herbaceous plants and vines.The irrigation system is designed to provide the water needed for the growth of the vegetation.The design of the intercepting drainage channel effectively prevents the heavy rainfall from causing soil erosion on the slope surface and completely realizes the ecological restoration of the abandoned quarry.