The application of the rockfall Susceptibility Index to Failure (SIF) to the case study of Varallo (VC)

This thesis addresses the issue of rockfall instability, focusing on identifying and analyzing areas prone to rockfall events. Specifically, it examines a slope in Varallo (VC, North-West Italy) that has experienced repeated rockfall phenomena over the years, posing risks to the buildings and the adjacent road at its base. Given the need to evaluate large areas, preliminary methods are essential to pinpoint zones requiring detailed analysis. To meet this need, the QPROTO plugin, integrated within QGIS, was used to quantitatively assess time-independent rockfall hazards across three-dimensional terrains using the Cone Method. This approach requires specific input angles, such as the energy angle (φp) and the lateral angle (α), which capture the complex dynamics of rock block movement along slopes. QPROTO generates raster maps that delineate potential invasion zones and quantify rockfall susceptibility. This research introduces a novel method to characterize the source areas, through the definition of the Susceptibility Index to Failure (SIF Index). The proposed framework provides QPROTO users with a systematic approach for estimating input parameters, improving the tool's accuracy and applicability. The effectiveness of this method is demonstrated through a case study in the north-western Italian Alps, showcasing its potential to enhance rockfall hazard assessments and support informed decision-making in risk management and planning. This study was conducted within the RETURN Extended Partnership and received funding from the European Union Next-GenerationEU (National Recovery and Resilience Plan—NRRP, Mission 4, Component 2, Investment 1.3—DD 1243 2/8/2022, PE0000005).