Study On Slope Mining Subsidence Monitoring And Prediction Based On 3D Laser Scanning Technology

When mining underground in mountainous area,if the mountain body is distributed above the working face,the characteristics of mining subsidence are more complex and uncertain than that of flat ground subsidence due to the common influence of topography,surrounding geographical environment and other factors.Once the surface has unpredictable displacement or deformation under the influence of various factors,it will affect the landmark buildings and the surrounding environment State environment damage,serious harm to the people's personal and property safety and ecological environment stability.Therefore,it is particularly important to monitor the slope with mining face below.In this paper,the influence of mining on the slope above the 10201,10202 and 6201 working face in Sucun is analyzed.The reliability of the model is verified by comparing the numerical simulation results with the measured data.Thus,the stability of the slope in the follow-up mining process is further evaluated by numerical simulation calculation.(1)The point cloud data of the slope in the study area are obtained,and the collected point cloud data are registered.The point cloud data of each period are unified into the same coordinate system,and the point cloud filtering algorithm based on slope is used to filter the data.The results show that the filtering efficiency reaches72.45%.After data interpolation,the DEM data of each period of slope is generated Comparing the data of the second and third phases with the first phase,with the mining of 10201 working face,the slope of area a is first affected by the mining.After the mining of 10202 working face,the mining influence of the slope of area B is more than that of area A.after the mining of both working faces,the slope of the two areas sinks about 5-6m,and the horizontal movement is also more obvious than that of the initial mining of 10201 working face As the slope increases,the whole slope shows a trend of moving to the south.(2)The numerical simulation model of the slope is established,in which the geometric model is constructed by collecting the initial point cloud data,and the constitutive model is based on the Mohr Coulomb model.Combined with the actual situation of the experimental site,the relevant parameters are obtained by referring to the existing physical and mechanical experimental results of the slope surface above Sucun 10201 working face.The probability integral method is used to predict the settlement at the position 20 m below the slope,and the displacement results in each direction are applied to the bottom of the slope model as boundary conditions for numerical simulation.(3)Slice the model,and compare the numerical simulation results of each period with the measured data.With the continuous mining of the working face and more influencing factors on the slope,the deviation of the two kinds of data gradually increases,but on the whole,the fitting situation is still reasonable.(4)By using the constructed slope model,the influence of 6201 working face mining on the slope is predicted and analyzed.The stability coefficient of a and B slope models is calculated by Swedish slice method and Janbu method and Bishop method respectively.The results show that the stability coefficient of the two slopes is always above 1.05 after 6201 working face mining,which is in a stable or basically stable state,Therefore,the mining of 6201 working face will not lead to the instability of the target slope.