scholarly journals Rheological properties and debris-flow modeling in a southern Italy watershed

2010 ◽  
Author(s):  
T. Bisantino ◽  
P. Fischer ◽  
F. Gentile ◽  
G. Trisorio Liuzzi
Keyword(s):  
Debris Flow ◽  
Rheological Properties ◽  
Southern Italy ◽  
Flow Modeling

scholarly journals Debris-flow susceptibility assessment through cellular automata modeling: an example from 15–16 December 1999 disaster at Cervinara and San Martino Valle Caudina (Campania, southern Italy)

2003 ◽  
Vol 3 (5) ◽  
pp. 457-468 ◽  
Author(s):  
G. Iovine ◽  
S. Di Gregorio ◽  
V. Lupiano
Keyword(s):  
Cellular Automata ◽  
Debris Flow ◽  
Urban Areas ◽  
Debris Flows ◽  
Soil Cover ◽  
Southern Italy ◽  
Landslide Risk ◽  
Campania Region ◽  
Optimal Values ◽  
Debris Flow Susceptibility

Abstract. On 15–16 December 1999, heavy rainfall severely stroke Campania region (southern Italy), triggering numerous debris flows on the slopes of the San Martino Valle Caudina-Cervinara area. Soil slips originated within the weathered volcaniclastic mantle of soil cover overlying the carbonate skeleton of the massif. Debris slides turned into fast flowing mixtures of matrix and large blocks, downslope eroding the soil cover and increasing their original volume. At the base of the slopes, debris flows impacted on the urban areas, causing victims and severe destruction (Vittori et al., 2000). Starting from a recent study on landslide risk conditions in Campania, carried out by the Regional Authority (PAI –Hydrogeological setting plan, in press), an evaluation of the debris-flow susceptibility has been performed for selected areas of the above mentioned villages. According to that study, such zones would be in fact characterised by the highest risk levels within the administrative boundaries of the same villages ("HR-zones"). Our susceptibility analysis has been performed by applying SCIDDICA S3–hex – a hexagonal Cellular Automata model (von Neumann, 1966), specifically developed for simulating the spatial evolution of debris flows (Iovine et al., 2002). In order to apply the model to a given study area, detailed topographic data and a map of the erodable soil cover overlying the bedrock of the massif must be provided (as input matrices); moreover, extent and location of landslide source must also be given. Real landslides, selected among those triggered on winter 1999, have first been utilised for calibrating SCIDDICA S3–hex and for defining "optimal" values for parameters. Calibration has been carried out with a GIS tool, by quantitatively comparing simulations with actual cases: optimal values correspond to best simulations. Through geological evaluations, source locations of new phenomena have then been hypothesised within the HR-zones. Initial volume for these new cases has been estimated by considering the actual statistics of the 1999 landslides. Finally, by merging the results of simulations, a deterministic susceptibility zonation of the considered area has been obtained. In this paper, aiming at illustrating the potential for debris-flow hazard analyses of the model SCIDDICA S3–hex, a methodological example of susceptibility zonation of the Vallicelle HR-zone is presented.

Progress in Debris Flow Modeling

2007 ◽  
pp. 59-77 ◽  
Author(s):  
Tamotsu Takahashi
Keyword(s):  
Debris Flow ◽  
Flow Modeling

Review Article Debris flow modeling: A review

1996 ◽  
Vol 8 (1) ◽  
pp. 1-35 ◽  
Author(s):  
K. Hutter ◽  
B. Svendson ◽  
D. Rickenmann
Keyword(s):  
Debris Flow ◽  
Review Article ◽  
Flow Modeling

A Study of Debris Flow Behaviors According to Rheometer Properties: Focused on the Hwangnyeong Mt. and Umyeon Mt.

2020 ◽  
Author(s):  
Hyeong-Jin Kim ◽  
Dae-Ho Yun ◽  
Yun-Tae Kim
Keyword(s):  
Debris Flow ◽  
Rheological Properties ◽  
Yield Stress ◽  
Flow Behavior ◽  
Front Velocity ◽  
Experimental Results ◽  
Small Scale ◽  
Water Mixture ◽  
Runout Distance ◽  
Two Samples

<p>A debris flow, a mass movement of soil and water mixture, is generally occurred by heavy rainfall during the rainy season in Korea. Because of climate change, the amount and frequency of rainfall has continually increased these days. Populated areas located in debris flow-prone mountainous areas are commonly subject to debris flow hazards. For this reason, it is necessary to analyze the characteristics of the debris flow behavior for the hazard mitigation. In this study, for two samples from Hwangnyeong Mt. and Umyeon Mt. in Korea, the vane-type rheometer test were performed to estimate the rheological property such as viscosity and yield stress and small-scale flume experiment was carried out to evaluate the characteristics of debris flow behaviors such as front velocity, runout distance and deposition volume. From the experimental results, rheological properties decrease with decreasing volumetric sediment concentration, and debris flow behavior gradually increased with decreasing rheological properties in the experiment. Additionally, in case of Hwangnyeong Mt. which has a high silt and clay fraction, the experimental results show that the amount of the front velocity, runout distance and deposition volume tend to increase higher than Umyeon Mt. as viscosity and yield stress decreased.</p>

GIS-assisted modelling for debris flow hazard assessment based on the events of May 1998 in the area of Sarno, Southern Italy: II. Velocity and dynamic pressure

2008 ◽  
Vol 33 (11) ◽  
pp. 1693-1708 ◽  
Author(s):  
G. Toyos ◽  
R. Gunasekera ◽  
G. Zanchetta ◽  
C. Oppenheimer ◽  
R. Sulpizio ◽  
...  
Keyword(s):  
Debris Flow ◽  
Hazard Assessment ◽  
Southern Italy ◽  
Dynamic Pressure ◽  
Debris Flow Hazard

scholarly journals Debris flow modeling at Meretschibach and Bondasca catchment, Switzerland: sensitivity testing of field data-based erosion model

2016 ◽  
Author(s):  
Florian Frank ◽  
Brian W. McArdell ◽  
Nicole Oggier ◽  
Patrick Baer ◽  
Marc Christen ◽  
...  
Keyword(s):  
Debris Flow ◽  
Field Data ◽  
Hazard Analysis ◽  
Flow Volume ◽  
Flow Modeling ◽  
Sensitivity Testing ◽  
Bed Erosion ◽  
Landslide Volume ◽  
Sediment Entrainment ◽  
Basal Shear

Abstract. Debris flow volumes can increase due to the incorporation of sediment into the flow as a consequence of channel-bed erosion along the flow path. This study describes a sensitivity analysis of the recently-introduced RAMMS debris flow entrainment algorithm which is intended to help solve problems related to predicting the runout of debris flows. The entrainment algorithm predicts the depth and rate of erosion as a function of basal shear stress based on an analysis of erosion measurements at the Illgraben catchment, Switzerland (Frank et al., 2015). Starting with a landslide-type initiation in the RAMMS model, the volume of entrained sediment was calculated for recent well-documented debris-flow events at the Bondasca and the Meretschibach catchments, Switzerland. The sensitivity to the initial landslide volume was investigated by systematically varying the initial landslide volume and comparing the resulting debris-flow volume with estimates from the field sites. In both cases, the friction coefficients in the RAMMS runout model were calibrated using the model where the entrainment module was inactivated. The results indicate that the entrainment model predicts plausible erosion volumes in comparison with field data. By including bulking due to entrainment in runout models, more realistic runout patterns are predicted in comparison to starting the model with the entire debris-flow volume (initial landslide plus entrained sediment). In particular, lateral bank overflow – not observed during this event – is prevented when using the sediment entrainment model, even in very steep (≈ 60–65 %) and narrow (4–6 m) torrent channels. Predicted sediment entrainment volumes are sensitive to the initial landslide volume, suggesting that the model may be useful for both reconstruction of historical events as well as the modeling of scenarios as part of a hazard analysis.

scholarly journals Rainstorm Magnitude and Debris Flows in Pyroclastic Deposits Covering Steep Slopes of Karst Reliefs in San Martino Valle Caudina (Campania, Southern Italy)

Water ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2274
Author(s):  
Guido Leone ◽  
Pasquale Clemente ◽  
Libera Esposito ◽  
Francesco Fiorillo
Keyword(s):  
Time Series ◽  
Debris Flow ◽  
Debris Flows ◽  
Southern Italy ◽  
Distribution Functions ◽  
Annual Rainfall ◽  
Standard Normal Distribution ◽  
Relative Significance ◽  
Campania Region ◽  
Steep Slopes

Debris flows that have occurred in the area of San Martino Valle Caudina (Campania, Southern Italy) are described by geomorphological and hydrological analyses, focusing on the recent event of December 2019. This area can be considered a key example for studying debris-flow phenomena involving the pyroclastic mantle that covers the karstified bedrock along steep slopes. A hydrological analysis of the time series of the maximum annual rainfall, of durations of 1, 3, 6, 12 and 24 h, was carried out based on a new approach to assess rainstorm magnitude. It was quantified by measuring the deviation of the rainfall intensity from the normal conditions, within a specified time period. As the time series of annual maxima are typically skewed, a preliminary transformation is needed to normalize the distribution; to obtain the Z-value of the standard normal distribution, with mean µ = 0 and standard deviation σ = 1, different probability distribution functions were fitted to the actual data. A specific boxplot was used, with box width Z = ±1 and whiskers length Z = ±2. The deviations from these values provide the performance of the distribution fits. For the normalized time series, the rates shown by the trends and relative significance were investigated for the available time series of 11 rain gauges covering the Western–Central Campania region. The most critical condition for the debris-flow initiation appears to occur when a severe or extreme rainfall has a duration ≥ 12 h. The trend analysis did not detect statistically significant increases in the intensity of the rainfall of duration ≥ 6 h.

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