Application Research Of 3D Laser Scanning Technology In Slope Monitoring

With the rapid development of China's economic construction,a variety of basic engineering facilities such as highways,railways,airports,water conservancy facilities,etc.,due to the needs of the engineering construction environment,especially in the rugged terrain of the southwest region,more and more artificial excavation of the slope.Slope once the occurrence of landslide disaster,not only to the country caused huge economic losses,but also to the people's life and property threats,in order to timely understand the stability of the slope,the slope monitoring work is essential.Due to the characteristics of rapid,non-contact,high spatial resolution and abundant data,3D laser scanning technology can be applied to slope deformation monitoring to solve the problems of traditional deformation monitoring data shortage,long monitoring period and failure to carry out overall deformation monitoring.Therefore,combined with the advantages of 3D laser scanning technology,this paper processes the slope point cloud and uses different deformation analysis methods to conduct deformation analysis.The main research contents are as follows:(1)Based on the analysis of the principle of distance measurement and Angle measurement in 3D laser scanning system,the key technologies of point cloud data acquisition and point cloud data processing in 3D laser scanning system on ground are studied.It mainly includes point cloud data acquisition and Mosaic method,point cloud denoising,point cloud compression and other post-processing technologies.(2)The traditional ICP algorithm has strict requirements on the initial attitude and slow registration speed.Principal component analysis is used to correct the initial attitude of the point cloud,and SAC-IA coarse registration +ICP fine registration algorithm is analyzed and studied.The accuracy and efficiency of the algorithm are verified by example data of Stanford lab Bunny and others.(3)The NURBS surface reconstruction technology is analyzed and studied.The DEM model of slope point cloud is constructed,and the NURBS surface reconstruction technology is suitable for the unclosed surface reconstruction.For the three-dimensional model constructed by NURBS surface,the GEOMAGIC software is used to carry out the comparative analysis between the original point cloud data and the model,and it is verified that the model has a high precision and can retain the detailed features of the slope completely.(4)The slope DEM model is used to analyze and compare the local and global deformation of the slope with the superposition of multi-temporal slope model and 2D profile line,and the feasibility of applying 3D laser scanning technology to slope deformation monitoring is verified by comparing with the traditional monitoring data.