The Use Of 3D Laser Scanning To Monitor And Predict Slope Stability Affected By Mining

At present,the deformation monitoring of slope affected by mining is transforming from single point measurement to surface measurement.The 3D laser scanning is one of the most efficient methods in the surface measurement,but point cloud processing based on single point or single line.There is great limitation and sidedness in deformation analysis as well as it is also a waste of point cloud data acquired by using 3D laser scanning.In addition,the research of mining subsidence prediction in plain areas is more mature in our country.However,there are relatively few studies on the slope prediction in hilly areas.Therefore,combining the 3D laser scanning with numerical simulation is used to predict the slope deformation affected by mining subsidence.The main works are as follows:(1)In slope point cloud preprocessing,an improved moving curved fitting(MCF)algorithm is proposed.After analysing the disadvantages of MCF algorithm,the MCF algorithm performance worse in point cloud contains low position non-ground points.Besides,the size of moving window and the selection of distance threshold are difficult to comfirm.Thus,the combining of RANSAC with MCF algorithm is proposed.Experimental results show that the improved MCF algorithm reduces the influence of low position non-ground points effectively,and the MCF algorithm is less affected by window's size and threshold.It can be seen that the improved algorithm is more stable.(2)In the calculation of slope deformable value,a multi-scale iterative nearest point(ICP)algorithm is proposed.In the finite element theory,the non-rigid transformation can be discretized as the rigid body transformation among elements.Thus,a multi-scale ICP algorithm is proposed to calculate the slope deformation.The simulation experiments and comparison experiments are designed to comfirm the reliability of multi-scale ICP algorithm.The result shows that the multi-scale ICP algorithm calculates slope deformation correctly,and the accuracy of vertical slope deformation calculation is higher than that of horizontal slope deformation calculation.(3)To construct the prediction model for slope deformation affected by mining,and predicting the slope deformation in Lvliang.The parameters of numerical model are optimized by the monitoring results.And the boundary conditions of numerical model are calculated by the probability integral method.After constructing the prediction model for slope stability,the slope stability is predicted for 201 working face and 202 working face mining.The result shows that the 201 working face and 202 working face have less impact on the slope stability,and the slope is in a stable or basically stable state...