Study On Monitoring Prediction And Stability Of Open-pit Slope

Jiepailing large open-air polymetallic ore is located in Yizhang,Hunan province,surrounded by a large number of residents.The mine found on June 22,2017 that the eastern slope of the mining area has formed a landslide in the stage of developing active activity under the condition of rainfall,which is in an unstable state and is a major source of safety hidden trouble in the mine.Therefore,the research on the slope of the Jiepailing open-pit is of great significance to ensure the safe production of the mining area.In this paper,the emergency Monitoring scheme and automatic monitoring system of artificial surface displacement are established on the slope of the eastern landslide and the dumping area,and go to the mine,to carry out the monitoring work.Through the summary and analysis of the monitoring data,this paper grasps the development dynamics of the slope,provides a realistic basis for the deformation control of the slope,and guarantees the safety of the personnel of the construction vehicle in the stage of slope reduction and the safety operation management of the drainage field in the eastern landslide of the mining field.In the prediction of slope deformation,a OGM(1,1)multivarnate model which can reflect the correlation between monitoring points is introduced,and the background value of grey model is optimized by adaptive mutation particle swarm algorithm,and the optimized OGM(1,1)model,GM(1,1)model,After the verhulst model and the nonlinear regression model,a suitable model is selected to predict the surface displacement of the slope of the drainage field,to judge the evolution stage and deformation trend of the slope of the drainage field,and to guide the drainage operation effectively.Aiming at the landslide in the eastern part of minning area,an improved limit equilibrium method considering rainfall action and gradual failure is established to evaluate the stability of landslide after engineering management and to ensure the safety of subsequent mining production work.The main conclusions of this paper are as follows:(1)Based on the monitoring data,it is determined that the landslide in the eastern part of the minning area belongs to the thrust load caused landslide,and the deformation change rate of the landslide decreases steadily during the engineering management of the slope reduction and loading,and stabilizes after September 2017.By using the improved Bishop method,the safety factors of landslide in slope reduction to+520m are 1.085 and 1.226 respectively,the results are more in line with the traditional limit equilibrium method,and the safety factor after treatment is higher than the standard of 1.15,which verifies the effect of slope reduction and load control.(2)The slope of the drainage field is currently in the creep deformation stage,and the results of predicting the surface deformation with a variety of monitoring models show that the accuracy of the grey model after optimizing the background value is significantly improved,and the model accuracy of the multivariable model OGM(1,N)in slope deformation prediction is better than that of other prediction models,and the prediction effect is It has high application value in slope deformation prediction.The prediction results show that the slope of the drainage field will still maintain the creep deformation state in February 2019,and there is no danger of damage without the interference of external factors.