Slope Stability Integrate Analyses: The Study Case of Mount Falcone (Central Italy)

Traditional technical solutions for slope stabilization are generally costly and very impacting on the natural environment and landscape. A possible alternative for improving slope stability is based on the use of naturalistic engineering techniques, characterized by a low impact on the natural environment and being able to preserve the landscape identity and peculiarities. In this work, we present an application of such techniques for slope stabilization along a greenway located in central Italy, characterized by an extraordinary natural environment. First, 22 potentially unstable slopes have been identified and examined; then, among these, two standard type slopes have been selected. For both of them, an appropriate naturalistic engineering work has been proposed and stability analyses have been carried out. These have been performed by considering different piezometric conditions and using two different approaches: (a) a classical deterministic approach, which adopts deterministic values for the mechanical properties of the soils neglecting any uncertainty, and (b) a probabilistic approach that takes into account a statistical variability of the soil property values by means of their probability density functions (PDFs). The geometry of each slope derives from a digital model of the soil with 1 meter resolution, obtained through Light Detection and Ranging (LiDAR) survey provided by the Italian Ministry of the Environment. The soil mechanical characteristics and their PDFs are derived from the geotechnical soil property database of the Perugia Province. Results show an increase in slope stability produced by the adopted countermeasures measured in terms of Factor of Safety ( F s ), Probability of Failure (PoF) and efficiency.

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Advanced distributed modelling of slope stability using root reinforcement and geostatistical parameterization of geotechnical soil properties

10.5194/egusphere-egu2020-13726 ◽

2020 ◽

Author(s):

Elena Benedetta Masi ◽

Anita Stagnozzi ◽

Silvia Stagnozzi ◽

Gianluigi Tonelli ◽

Francesco Veneri ◽

...

Keyword(s):

Slope Stability ◽

Central Italy ◽

Image Interpretation ◽

Test Site ◽

Rain Gauge ◽

Rainfall Event ◽

Unit Weight ◽

Future Research ◽

Time Step ◽

Soil Thickness

A physically based model for shallow landslide triggering (HIRESSS &#8211; HIgh REsolution Soil Stability Simulator) was applied in a 100 km2 test site in Central Italy (Urbino, Marche region). The objectives were assessing &#160;the influence of additional cohesion provided by roots and testing the effectiveness of a geotechnical characterization performed in an another area, but on similar lithologies.We performed two different simulations considering the rainfall event of January-February 2006, which triggered 14 landslides in the area. For both the simulations, rainfall data were fed into the model using the measurements at hourly time step of a nearby rain gauge station, while soil thickness was estimated using a state-of-the-art empirical model based on geomorphological parameters derived from curvature, slope gradient, lithology and relative position within the hillslope profile. Geotechnical input data were varied among the two simulations. In the first one, a few in-situ and laboratory tests were performed to characterize the main lithologies, while the remaining lithologies were characterized using literature data. In the second simulation, the main geotechnical and hydrological parameters (cohesion, internal friction angle, soil unit weight, hydraulic conductivity) were fed into the model using a geostatistical characterization performed on hundreds of measurements carried out in another Italian region, with similar lithologies. Furthermore, in the second simulation the additional cohesion provided by the plant roots was also taken into account.The results obtained with the two simulations were validated considering the landslide dataset collected by field work and image interpretation shortly after the rainfall event studied. We discovered that the second simulation provided much more reliable results, with the areas surrounding the landslide locations characterized by much higher values of failure probability.The outcome is very important to address future research in distributed slope stability modelling because it proved that: (i) additional root cohesion is an important factor that can be used to get more reliable results; (ii) when in need of characterizing the geotechnical parameters of the study area, instead of using just a few measurements performed therein, it is preferable to integrate also data coming from different areas but with similar lithologies if they were robustly characterized in geostatistical terms purposely for distributed slope stability studies.

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A strategy for GIS-based 3-D slope stability modelling over large areas

Geoscientific Model Development Discussions ◽

10.5194/gmdd-7-5407-2014 ◽

2014 ◽

Vol 7 (4) ◽

pp. 5407-5445 ◽

Cited By ~ 3

Author(s):

M. Mergili ◽

I. Marchesini ◽

M. Alvioli ◽

M. Metz ◽

B. Schneider-Muntau ◽

...

Keyword(s):

Slope Stability ◽

Landslide Susceptibility ◽

Slope Failure ◽

Computing Time ◽

Central Italy ◽

Shallow Landslides ◽

Landslide Susceptibility Mapping ◽

Deterministic Models ◽

Average Value ◽

Slip Surfaces

Abstract. GIS-based deterministic models may be used for landslide susceptibility mapping over large areas. However, such efforts require specific strategies to (i) keep computing time at an acceptable level, and (ii) parameterize the geotechnical data. We test and optimize the performance of the GIS-based, 3-D slope stability model r.slope.stability in terms of computing time and model results. The model was developed as a C- and Python-based raster module of the open source software GRASS GIS and considers the 3-D geometry of the sliding surface. It calculates the factor of safety (FoS) and the probability of slope failure (Pf) for a number of randomly selected potential slip surfaces, ellipsoidal or truncated in shape. Model input consists of a DEM, ranges of geotechnical parameter values derived from laboratory tests, and a range of possible soil depths estimated in the field. Probability density functions are exploited to assign Pf to each ellipsoid. The model calculates for each pixel multiple values of FoS and Pf corresponding to different sliding surfaces. The minimum value of FoS and the maximum value of Pf for each pixel give an estimate of the landslide susceptibility in the study area. Optionally, r.slope.stability is able to split the study area into a defined number of tiles, allowing parallel processing of the model on the given area. Focusing on shallow landslides, we show how multi-core processing allows to reduce computing times by a factor larger than 20 in the study area. We further demonstrate how the number of random slip surfaces and the sampling of parameters influence the average value of Pf and the capacity of r.slope.stability to predict the observed patterns of shallow landslides in the 89.5 km2 Collazzone area in Umbria, central Italy.

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Geophysical and geologic surveys of the areas struck by the August 26th 2016 Central Italy earthquake: The study case of Pretare and Piedilama

Journal of Applied Geophysics ◽

10.1016/j.jappgeo.2017.07.016 ◽

2017 ◽

Vol 145 ◽

pp. 17-27 ◽

Cited By ~ 12

Author(s):

S. Imposa ◽

F. Panzera ◽

S. Grassi ◽

G. Lombardo ◽

S. Catalano ◽

...

Keyword(s):

Central Italy ◽

Central Italy Earthquake ◽

Study Case

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Assessing desertification vulnerability on a local scale: the Castelporziano study case (central Italy)

RENDICONTI LINCEI ◽

10.1007/s12210-014-0362-5 ◽

2014 ◽

Vol 26 (S3) ◽

pp. 421-450 ◽

Cited By ~ 4

Author(s):

Claudia Trotta ◽

Patrizia Menegoni ◽

Francesco Massimo Manfredi Frattarelli ◽

Massimo Iannetta

Keyword(s):

Central Italy ◽

Local Scale ◽

Study Case

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The Contribution of Terrestrial Laser Scanning to the Analysis of Cliff Slope Stability in Sugano (Central Italy)

Remote Sensing ◽

10.3390/rs10091475 ◽

2018 ◽

Vol 10 (9) ◽

pp. 1475 ◽

Cited By ~ 3

Author(s):

Paolo Mazzanti ◽

Luca Schilirò ◽

Salvatore Martino ◽

Benedetta Antonielli ◽

Elisa Brizi ◽

...

Keyword(s):

Slope Stability ◽

Laser Scanning ◽

Limit Equilibrium ◽

Water Pressure ◽

Central Italy ◽

Point Clouds ◽

Stability Conditions ◽

Seismic Action ◽

3D Point Clouds ◽

Geomechanical Analysis

In this work, we describe a comprehensive approach aimed at assessing the slope stability conditions of a tuff cliff located below the village of Sugano (Central Italy) starting from remote geomechanical analysis on high-resolution 3D point clouds collected by terrestrial laser scanner (TLS) surveys. Firstly, the identification of the main joint systems has been made through both manual and automatic analyses on the 3D slope model resulting from the surveys. Afterwards, the identified joint sets were considered to evaluate the slope stability conditions by attributing safety factor (SF) values to the typical rock blocks whose kinematic was proved as compatible with tests for toppling under two independent triggering conditions: hydrostatic water pressure within the joints and seismic action. The results from the remote investigation of the cliff slope provide geometrical information of the blocks more susceptible to instability and pointed out that limit equilibrium condition can be achieved for potential triggering scenarios in the whole outcropping slope.

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Remnants of naturalness in a reclaimed land of central Italy

Italian Botanist ◽

10.3897/italianbotanist.11.62040 ◽

2021 ◽

Vol 11 ◽

pp. 9-30

Author(s):

Gianmaria Bonari ◽

Tiberio Fiaschi ◽

Emanuele Fanfarillo ◽

Francesco Roma-Marzio ◽

Simona Sarmati ◽

...

Keyword(s):

Environmental Changes ◽

Land Use Changes ◽

Central Italy ◽

Point Of View ◽

Natural Habitats ◽

Reclaimed Land ◽

Species Of Conservation Concern ◽

Study Case ◽

Conservation Concern ◽

Eurasian Species

Wetlands are among the most fragile habitats on Earth and have often undergone major environmental changes. As a study case in this context, the present work aims at increasing the floristic knowledge of a reclaimed land now turned into an agricultural lowland with scarce patches of natural habitats. The study area is named Piana di Rosia, and it is located in southern Tuscany (Italy). The compiled checklist consists of 451 specific and subspecific taxa of vascular plants. The life-form spectrum shows a predominance of hemicryptophytes, followed by therophytes. The chorological spectrum highlights a co-dominance of Euri-Mediterranean and Eurasian species along with many widely distributed species. The checklist includes seven species of conservation concern, three Italian endemics (Crocus etruscus Parl., Polygala vulgaris L. subsp. valdarnensis (Fiori) Arrigoni, and Scabiosa uniseta Savi), 41 alien species, 21 segetal species, and 11 aquatic macrophytes of which five helophytes and six hydrophytes. This study suggests that irreversible land-use changes in wetlands can lead towards a simplification of the flora. However, despite the deep transformations that the former wetland has undergone, the presence of some aquatic and protected taxa is interesting. From a conservation point of view, the natural value of this agricultural area could be enhanced and its current management partly reconsidered, thus preserving the remnants of naturalness present.

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