Abstract:Due to the large scope of safety management of tailings dam and the special mountainous environment, traditional surveying and mapping means are difficult to carry out, and the deformation and displacement data of tailings dam can only be obtained through single or multi-point monitoring. Therefore, this paper proposes a tailings dam deformation monitoring and analysis method based on UAV photogrammetry, which collects the three-dimensional geographic information data of two phases of tailings dam by UAV. The collected data of the two periods were reconstructed in three dimensions and the point cloud model was generated. The point cloud model of the two periods was compared and analyzed by using the three dimensional spatio-temporal comparative analysis technology of geographic information. The results show that the method can realize the comprehensive monitoring of tailings dam from point to surface, and the monitoring accuracy can reach cm level, which provides a basis for the macro deformation monitoring of tailings dam and the rapid verification and safety inspection of abnormal deformation area.