Stability Analysis Of Open Pit Mining Based On FLAC 3D

The steel industry is a pillar industry of China's national economy and a basic industry related to national economy and people's livelihood.Open-pit mining,as the main source of steel,has an important role in practical engineering.However,there are serious safety hazards such as landslides and collapses during open-pit mining.Once a security accident occurs,there is no way to recover casualties and property damage.In order to avoid the occurrence of the above-mentioned disasters,scientific researchers continue to carry out research on the prediction and prediction of slope disasters.In the study of slope prediction and prediction,the first choice is to analyze the slope stability.In this paper,the "11-1005 landslide" of Nanfen open-pit iron mine was selected as the research object,combined with FLAC 3D numerical simulation software for slope stability analysis.The stability analysis results provide a design basis for slope safety mining and a theoretical basis for the prediction and prediction of slope disasters,which is of great significance to the safe mining of ore in the iron and steel industry.This paper firstly analyzes the necessity of slope mining stability analysis,and expounds the research status of open pit slope mining,landslide model test and numerical simulation technology at home and abroad.The engineering overview and natural geographical conditions of the Nanfen open-pit iron mine were established,and a geomechanical model test was constructed based on the similar principle;then FLAC 3D 6.0 was used to establish a numerical simulation model.The geomechanical model test,numerical simulation analysis results,and landslide damage Through comparison and analysis,the main influencing factors of the landslide were obtained.Finally,FLAC 3D 6.0 was used to formulate numerical simulation tests of two mining schemes for typical sections in Nanfen Open-pit Iron Mine.The feasibility of the two different schemes was analyzed and verified.The feasibility and effectiveness of FLAC 3D in practical applications.The main contents and research results of this article are as follows:(1)Select the 298 m platform to 370 m platform of "11-1005 landslide",build a geomechanical model with gypsum board as the simulation material,load the geomechanical model through the deep underground engineering model test system,and restore the "11-1005 landslide" During the study,it was found that the landslide was mainly abruptly changed by the displacement of the bottom of the slope,which led to the destruction of the entire sliding body.The destruction process of the entire sliding body is not continuous due to the presence of the anchor cable.Therefore,the selection of monitoring points in actual engineering should be placed in.At the same time,it was concluded that the unreasonable excavation was the main reason for this landslide.(2)Use FLAC 3D software to construct a numerical model from platform 298 m to platform 370 m,and simulate the mining of the slope,and compare the simulation results with the geomechanical model,and it is difficult to observe the anchor cable part in the geomechanical model Conducted a key analysis.Comparative analysis shows that the anchor cable has a great influence on the vertical displacement of the sliding body,which makes the displacement of the sliding body occur discontinuously,and the displacement at the top of the slope is greater than the bottom of the slope,which ensures the safety of the slope to a certain extent.Geomechanical model tests can intuitively reproduce the process of slope failure.Numerical analysis can focus on some complex and difficult to restore locations.The joint analysis of the two will provide stability for the "11-1005 landslide" in Nanfen Open-pit Iron Mine.The analysis provided experimental data.(3)Select the typical section in Nanfen open-pit iron mine,use FLAC 3D to establish a numerical model,and formulate two mining methods: step mining and stepless mining The comparative analysis of the maximum unbalanced force,slope safety factor,slip line,maximum principal stress and displacement field in the two mining methods can show that in large-scale open-pit mining,it is more conducive to mining platform Security.At the same time,it proves that FLAC 3D can carry out effective and accurate numerical analysis of open slope mining,and can provide scientific guidance for slope mining.