Abstract:
Rock fracture properties contribute significantly to rock slope stability across a range of lithological settings in New Zealand, and globally. However, there is often limited access to outcrops due to the hazards involved, which limits traditional field exposure mapping/logging. This project uses Unmanned Aerial Vehicle (UAV) photogrammetry to model selected rocky cliffs along Auckland’s coast and then uses Sirovision software to delineate and model fractures. Fracture properties extracted from Sirovision can then be used for Discrete Fracture Network (DFN) modelling, which was used to assess the stability of the exposed slopes. The results show that this can be an effective approach for conducting realistic rock stability modelling at poorly accessible sites. However, there are limitations to the workflow of UAV photogrammetry and Sirovision. In particular, it is problematic to characterise fracture roughness, waviness, strength and spacing in Sirovision, given the resolutions involved. Nevertheless, the application of this method has great potential for rock stability modelling of natural slopes, tunnels, quarries, mines, or excavations where accessibility is an issue.
