Abstract:Abstract:Research purposes: Through the research of UAV image 3Drailway survey technology,we can cope with the problems of low efficiency of railway surveying in Tibet - Sichuan - Yunnan,and local dangerous area survey precision not to meet the requirements of the design, and at the same time reduce the security risk investigation. This paper systematically describes the classification and application of UAV,and the basic principles of three - dimensional image technology. Based on a large number of on - site tests,studies the application of the UAV3D imaging technology in a wide range of geological route selection, tunnel exploration and rockfall, landslides, mudslides and other adverse geological survey. Compared with the traditional survey methods,the advantages of 3D image technology in the investigation of safety,efficiency and precision of the unmanned aerial vehicle are analyzed. Research conclusions: ( 1 ) The UAV 3D imaging technique can complete rockfall volume, coordinate calculation of middle strata shape measurement and landslides, mudslides and geometrical characteristics measurement and other investigation work. (2) The UAV 3D imaging technology can complete the structural identification, lithologic identification and other regional geological survey. (3 ) The UAV 3D imaging technology can improve the accuracy and efficiency of reconnaissance survey. (4) The UAV 3D imaging technology can be widely used in railway survey of complex mountainous area.