The Analysis And Evaluation Of High Rock Slope Stability In Lanying Xu Open-pit Iron Mine

There is a very important research significance in the study of the stability ofhigh and steep slope in open-pit mining, due to its close relationship between thesafety in mines production, the economic benefit and sustainable development ofmines.This thesis relided on the high and steep slope of LanYingXu open-pit ironmining in PanZhiHua, for the existence of weak structural plane and joints,we didsome resarch in the development of the deformation failure mechanism anddevelopment of slope. Then use equilibrium method and shear strength reductionmethod which based on the discrete element method to qualitatively andquantitatively evaluate the slope stability，the main content of the research includefollwing:1、For the commonly existence of joints and fissures in rock slope of LanYingXuopen-pit iron mine, Combined with the geologic site condition and the specificsituation of the slope,we investigate the detail lines along the slope and use the digitalfine description of rock mass (3D laser scanning) method to analysis thecharacteristics in slope such as weak plane (amphibole schist ω6) and joints. And setthe statistics of fault weak surface and joints which control the stability of slope inclasssification.2、Based on the outdoor investigation and indoor test, we confirm the elementsthat affect slope stability include the material and structure of rock mass, groundwater,earthquake and blasting. According to the structure features of the engineeringgeological profile we find following possibility failure mode that may infer the slope.The upper slope may present planar bedding sliding along ω6or clay interactions, thelower slope will be shearing cutted the jointed rock mass which seems like compositeplane shear failure. Or when joint rock mass damage, destruction along the main rolejoint of the slope,called complex plane shear failure in joint rock.3、Take the sample collected from mine, we did the indoor uniaxial compression, triaxial compression and vibration triaxial test.Combine the the experience ofpredecessors and laboratory test results,for the rock stability calculation of materialparameters and structural plane basic parameters recommended indexes are given.Use the residual thrust method and Sarma method in limit equilibrium method tocalculate the whole and part of the slope, Sarma method makes the criterion.4、Use the shear strength reduction method which based on the discrete elementmethod to analysis the stablity of jointed rock slope. To determine whether the slopeis in the limiting state or not by reducing the shear strength parameters of slope rockmass (c、), and get the stability coefficient. At the same time, according to theinformation such as the strain and displacement to search which part may be instable.5、The combine results of above methods shows that there’s a consistent in bothnumerical simulation and the limit equilibrium method. Based on the results putforward some protection, control measures such as optimize the slope foot, cuttingslope to reduce load to be safe and economic. This reflect that the research hasrealistic meaning and reference value for the high slope in open-pit mine.