An integrated remote sensing - numerical modelling approach for the characterization of slope damage
Prof. Davide Donati
July 11th
h. 12:00
Room Trasporti (viale del Risorgimento 2, Bologna)
Abstract: The stability of slopes is largely controlled by geological structures, lithology, rock mass quality, and hydrogeological conditions. The occurrence of exogenic and endogenic processes, such as seismic activity, rock mass and joint alteration and weathering, erosion, anthropogenic activities, may weaken the rock mass forming the slope and promote 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 that can be comprehensively referred to as “slope damage”. The characterization of slope damage features can be undertaken using state-of-the-art remote sensing techniques, including terrestrial and airborne laser scanning (TLS and ALS), terrestrial digital photogrammetry (TDP), structure-from-motion (SfM), high-resolution photography, infrared thermography (IRT), and hyperspectral imaging (HSI). Additionally, advanced numerical modelling techniques, including Distinct Element Method (DEM), Hybrid Finite- Discrete Element Method (FDEM), and lattice-spring scheme methods, is shown to provide new insights on the style of deformation and the factors that control the stability and failure of slopes. Using various case studies, it is demonstrated that the interaction of geological factors and processes, such as intact rock and rock mass quality, geological structures, slope morphology, glacier and stream erosion, and groundwater, controls the formation of slope damage. In turn, the progressive accumulation of slope damage enhance the kinematic freedom of potentially unstable slopes, ultimately promoting failures. It has been demonstrated that characterizing the distribution and evolution of slope damage features observed in the field using remote sensing datasets and numerical modelling, potentially allows reinterpretation of slope deformation and failure mechanisms of landslides in rock and soil. It is concluded that slope damage mapping techniques should be included as a standard procedure in rock slope characterization, and that the potential effects on the slope kinematics should also be addressed to realistically assess the long-term stability of rock slopes.