Research On Structure Deformation In Mining Area Under The Monitoring Of 3D Laser Scanning

Three dimensional laser scanning technology is a new technology in the field of surveying and mapping science and technology. It has been applied to all sectors of production and life thanks to its advantages such as rapid, accurate, non-contact measurement. With the social and economic development in China, there is an increasingly growing demand for energy. At the same time, the destruction of the surface building caused by underground coal mining is becoming more and more serious. The construction of the mining area is related to the local social and economic development, production and life. Therefore, it is of great significance to effectively grasp the deformation of the mining area building by periodic monitoring and analyzing so as to guarantee the safety of the building. In this paper, the 3D laser scanning technology is used to study the deformation monitoring of the mining area building and structure. The main contents are as follows:(1) According to the basic principle and precision formula of laser scanner, the elevation and slope accuracy theoretical formula of laser scanning in actual engineering application has been deduced. In this paper, the VZ-1000 Riegl scanner is used as an example and the accuracy calculation is carried out with a variety of specific conditions. The application feasibility of the laser scanning in the mining area construction deformation monitoring is proved by the comparison with relevant codes of allowable deformation value for the building. This paper puts forward a technical approach for improving the accuracy of laser scanning by analyzing the factors affecting accuracy of elevation and tilt.(2) In the study of deformation extraction method, based on the problem of poor anti-noise between plane and curved surface fitting, this paper puts forward a suitable threshold to improve plane fitting by analyzing the point cloud data distribution characteristics, with the adoption of RANSAC algorithm. In addition, the improved algorithm of surface fitting based on RANSAC algorithm is demonstrated. The calculation methods of the gravity center of the irregular and hole point cloud and the surface mutation extraction algorithm based on Delaunay subdivision ICP registration are put forward. Besides, the extraction of point cloud features is realized based on the vector change of point cloud approach.(3) The construction deformation monitoring affected by mining subsidence in Yangdong and Wannian mine which are located in the Fengfeng mine were used as an engineering example in this paper. The data of the research objects were collected by the 3D laser scanner. The corresponding deformation is extracted and analyzed by adopting appropriate algorithm and point cloud slicing approach, and it shows that the algorithm of this paper is feasible to extract the construction deformation in the mining area.