Thermohydraulic Numerical Modeling of Slope-Vegetation-Atmosphere Interaction: Case Study of the Pyroclastic Slope Cover at Monte Faito, Italy
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 149, Issue 11
Abstract
Flow-like landslides are recognized to be the most destructive slope movements and to threaten human life. They may occur in several geological settings, as is the case of the pyroclastic soil covers resting on either igneous, or carbonate, bedrocks. The pyroclastic soil strata involved in these shallow landslides typically are partially saturated over the whole year. Intense rainfall, considered at hourly time scale, represents the triggering factor because it causes the decrease in matric suction and the consequent decrease in soil shear strength. However, it is recognized as the role of the hydromechanical slope behavior, the vegetation cover, and the geomorphological irregularities on shallow landslide hazard. These factors should be properly simulated in physically based predictive models of the failure onset to set up a reliable early warning system (EWS). This paper presents a new coupled thermohydraulic modeling of a pyroclastic soil cover in Campania, accounting for several slope factors that may predispose landslide activation, including the geomorphological local irregularities. The Mount Faito test site, in the Lattari Mountains (Southern Italy), has been adopted as a prototype slope for the geomorphological and hydromechanical scenarios of reference because of the extensive field and laboratory characterizations of the soil strata already available from previous studies. Once validated with these data, the numerical model has been used to estimate the slope response to critical rainfall scenarios. Such numerical estimations have been then compared to the instability predictions currently provided by empirical approaches, defined in terms of the intensity and duration of rainstorms threshold of shallow landslide activations. By comparison between the empirical and physically based approaches, the crucial role of antecedent slope hydraulic conditions and the geological setting for implementing reliable EWS, reducing false alarms, is proved.
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Data Availability Statement
Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
The authors wish to acknowledge the support of the European Commission via the Marie Skłodowska-Curie Innovative. Training Networks (ITN-ETN) project TERRE, “Training Engineers and Researchers to Rethink Geotechnical Engineering for a Low-Carbon Future” (H2020-MSCA-ITN-2015-675762). Indeed, the authors have developed this work in the framework of the project titled “New technologies for in-time prediction of flowslide occurrence” (TEMPO). This project was conducted in the framework of the STAR program, financially supported by UniNA and Compagnia di San Paolo. The authors thank Prof. Antonio Santo, who provided the geological and stratigraphic data characterizing slope cross-sections, serving as the basis of the analyses carried out.
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Journal of Geotechnical and Geoenvironmental Engineering
Volume 149 • Issue 11 • November 2023
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© 2023 American Society of Civil Engineers.
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Received: Aug 5, 2022
Accepted: Jun 26, 2023
Published online: Aug 28, 2023
Published in print: Nov 1, 2023
Discussion open until: Jan 28, 2024
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