Study On The Stability Of High Rock Slope In Dulong Zinc And Indium Outcrop Mining

The slope of open pit mine has the characteristics of high,steep and deep.With the continuous mining of the mine,the height and slope of the slope increase,and the formation lithology,structure and joint fissure of the mining area are more complex,which will lead to the increasingly serious problem of slope stability.For the long-term development of mine,it is necessary to carry out dynamic monitoring and adjustment of mining and stripping scheme to ensure the stability of high rock slope.In this paper,the bedding high rock slope of Dulong Zinc Indium Mining is taken as the research object.Through data collection and field geological mapping,the geological background and engineering geological problems in the research area are systematically explained.Perform borehole cataloging,in-situ tests,point load tests,indoor tests,and joint fissure surveys in the study area,and use the rock mass quality index RMR classification method to obtain the physical and mechanical parameters of the study area slopes,and verify the rationality of the parameter values.Using borehole data,orthographic projection,and RQD to determine the potential sliding surface（zone）in the study area and select three typical sections,the limit equilibrium method is used to calculate the stability of the current and final slopes under natural,rain,and rainfall plus blast conditions.,Establish a practical geological model,use FLAC^3D numerical simulation software to simulate the current status and end conditions of the slope,and make stability evaluation.The main results obtained are as follows:1.177 fissures were obtained through actual field measurements.The disc fissure model was used to generate a three-dimensional spatial distribution model of fissures in the study area,and the development of dominant fissures was obtained by combining the isodensity map of the fissures.The instability of the joints in the research area was obtained by the slope flat projection.The wedge-shaped body,based on the combination of the sampling depth of the drilled fracture zone and the RQD of the core,comprehensively determines that there are two potential sliding surfaces（bands）in the current slope of the study area.Finally,there is a potential sliding surface（band）of H3 landslide in the study area.2.The H3 landslide that has occurred in the study area is selected,and the homogeneous and heterogeneous geological models are established based on the borehole data to verify the physical and mechanical parameters of rock and soil in the study area by numerical simulation.it is found that the displacement of the heterogeneous geological model is consistent with the actual monitoring.It shows that the location of the potential slip surface and the related physical and mechanical parameters determined by the comprehensive analysis of borehole sampling depth,core RQD,slope stereographic projection and three-dimensional fracture disk model of H3 landslide are reasonable.3.Using the simplified Bishop method and simplified Janbu method to analyze the two-dimensional stability of the current slope and the final slope of the study area under the three conditions of natural,rainfall,and blasting.Less stable,prone to landslides;the overall stability of the slope at the end of the study area is good,except for the 2-2′section,which tends to be unstable under rainfall conditions.4.The FLAC^3D numerical simulation software is used to simulate the slope in the study area under three working conditions of natural,rainfall and blasting,and the stability of the current slope and the final slope are calculated respectively.The simulation results show that the present slope is in a stable state under natural conditions,and the slope is unstable under rainfall and blasting conditions,and the final slope is stable under natural conditions,and the maximum displacement is32.20cm under rainfall conditions.the shear stress at the foot of the slope increases obviously,and the slope is unstable under 1220 platform,and the slope is unstable under blasting and rainfall conditions.