Research On Comprehensive Early Warning And Prevention Technology Of Creep-Large Deformation In High And Steep Slope Of Fushun West Open-pit Mine

During the hundred years mining process of Fushun West open-pit mine,a high and steep slope with creep-large deformation is formed in southern slope,which the comprehensive early warning and prevention technology research has become a major issue affecting the safe production of Fushun West open-pit mine.The compression creep experiments of weak layer soft rock were carried out in order to study the mechanism of creep-large deformation,the results show that the conventional stress-strain curve of soft rock indicates a clear tendency of the conversion from elasto-brittle-plastic to elasto-plastic,and it is also highly sensitive to confining pressure.According to the principle of creep damage,the strain softening(S-S)characteristics of the M-C model have been taken into the creep damage equation,BNSS damage model of soft rock with creep-large deformation is established,andthe attenuate law of the cohesion and friction angle of soft rock with the expansion of creep strain is obtained,which is verified by numerical simulation.The boundary of the rear edge(crack),left and right,bottom and front edge(floor heave)of the large deformation body are comprehensively determined by different monitoring technologys,which include Interferometric Synthetic Aperture Radar monitoring technology(In SAR),Slope Stability Radar monitoring technology(SSR),IMS microseismic monitoring technology,borehole camera monitoring technology,D-In SAR,MAI remote sensing monitoring technology.In order to infer the possible faults and fracture zones of high and steep slopes and determine the stage of landslide deformation,the infrared thermal imager and SSR are used to monitor the large deformation slopes in the West Open-pit mine.By using the finite element method and RFPA software,the slope failure mode under different working conditions is simulated and verified,which include current status,design and backfill of the presser foot in the West Open-Pit mine,it shows that the characteristic of the failure mode of the large deformation slope in the West Open-Pit Mine is "Pull-Slip-Shear".Comprehensive control measures such as "sub-regions,sub-sections","effective waterproofing",and "adjustment of mining layout" were implemented.Specifically,anti-slide pile engineering was adopted for the installation area of pithead oil factory,grouting engineering was adopted for the crack zone,flood control system was constructed for groundwater,and backfilling presser foot engineering was implemented for the main deformation area.On this basis,the overall mining layout of the open-pit mine has been adjusted.The solution to the safety problems of high and steep slopes in West Open-Pit mine has significant economic,environmental and social benefits.It includes protecting the surroundingbuildings(structures),public facilities and the safety of residents' lives and property,constructing a better living environment,promoting the coordinated development of mine and city,and also maintaining social stability.Meanwhile,as various types of open-pit mines gradually extend deeper,the safety of high and steep slopes will also become a common problem of all those open-pit mines.The research on comprehensive early warning and prevention technology of high and steep slopes in Fushun West Open-pit Mine can provide the technical support and engineering demonstration for the safety of this type of mine.There are 146 pictures,8 tables,and 148 references in this dissertation.