The characterization of slope damage using an integrated remote sensing-numerical modelling approach

The stability of slopes is controlled by geological structures, lithology, rock mass quality, and hydrogeological conditions. Additionally, the occurrence of exogenic and endogenic processes may weaken the rock mass forming the slope, promoting instability. Slope deformation is associated with the formation of a range of internal and external features, such as tension cracks, rock mass dilation, and rockfall, referred to as “slope damage”. In this research, state-of-the-art remote sensing techniques, including terrestrial and airborne laser scanning, digital photogrammetric methods, high-resolution photography, infrared thermography, and hyperspectral imaging, are employed to characterize slope damage features both spatially and temporally. New innovative measures of slope damage are introduced. Processes and mechanisms controlling the formation and distribution of slope damage are highlighted at selected major landslides using advanced numerical modelling techniques, including distinct element, hybrid finite-discrete element, and lattice-spring scheme methods. Innovative uses of remote sensing data as a constraint for 3D modelling of slope damage are presented. This research clearly demonstrates that several geological factors control the formation, distribution, and evolution of slope damage, with the results being summarised in a slope damage interaction matrix format. It is clearly shown that the characterization of slope damage, combined with remote sensing datasets and numerical modelling results, allows reinterpretation of slope deformation and failure mechanisms of selected landslides in rock and soil. The recognition and importance of interaction between kinematics, geological structures and damage on the long-term evolution of the Downie Slide and Hope Slide (BC) is clearly demonstrated. The important role of brittle fracture propagation on the kinematics of the 2014 San Leo landslide (Italy) on the 2014 slope failure is highlighted. The geomorphic controls on external spatio-temporal slope damage at the Ten Mile Slide (BC) is emphasised using new damage measures. This research highlights the need to include slope damage mapping techniques as a standard procedure in rock slope characterization, in order to obtain important insights on the mechanisms and processes that affect the stability, deformation, and failure of rock slopes.