Assessment of Rockfall-Infrastructure Interaction: A Case Study of a Viaduct in Northeastern Italy

Determining the interaction between landslides and infrastructure is a complex task, given the wide variability in landslide types and infrastructure designs. Accurate risk assessment must consider landslide characteristics,structural vulnerability, and exposure to risk. Events such as sudden rock falls, topples, or debris flows are often almost unpredictable and leave virtually no time for intervention. Assessing the risks associated with these rapid phenomena is critical to understanding their potential to cause devastating impacts. This article examines a case study occurred in Northeast Italy in early 2024 when a large portion of material suddenly collapsed, impacting a railway, initially, and then a road viaduct. The incident caused severe damage and the closure of both routes for months.Existing mitigation measures failed due to the material's volume and speed. In addition to a detailed case study description, this work also presents findings using the QPROTO plugin for QGIS, which was used tosimulate the event. Finally, the consequences of the possible detachment of two other rock masses identified as unstable during an inspection following the event were assessed.Advanced modelling tools are crucial for improving risk evaluation and understanding landslide-infrastructure interactions.