Evaluation of the stability of rocky slopes using 3D point clouds obtained from an unmanned aerial vehicle

In this work, a methodology proposed for the semiautomatic identification of discontinuities and the later kinematic and stability analyses is described through its application to a rocky railway line cutting. Image acquisition has been performed using a six-rotors unmanned aerial vehicle for their subsequent photogrammetric restitution applying of the digital technique Structure from Motion (SfM) by means of the software Agisoft Metashape that provides a 3D point cloud. From this 3D point cloud, four discontinuity sets (J(1), J(2), J(3) and J(4)) affecting the cutting have been identified using the open source software Discontinuity Set Extractor (DSE). Finally, kinematic and stability analyses of the potential block failures controlled by the discontinuities identified in the cutting. The results show three potential wedge and planar failures that have been qualitatively validated trough the geometric analysis of the 3D point cloud.