PSI - Issue 62

Salvatore Misiano et al. / Procedia Structural Integrity 62 (2024) 576–584 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

581

6

Different maps, containing the values of the properties to use in the SLIP model are created, based on the information obtainable from regional geoportals, i.e., DEM and shapefiles that contain polygons with various classes, related to soil, land use, etc. The DEM, in this case 10x10 m, allows to process elevation, slope, and aspect angles. The latter is particularly useful in creating cluster of points that refer to the same landslide body. Furthermore, the shapefile of soil class polygons is helpful in creating Soil Units (Gatto and Montrasio 2023), which are subsequently associated to various characteristic soil parameters, which, for instance, could be the friction angle, the cohesion and the and λ experimental parameters to use in SLIP. Regarding the rainfall, these data could be obtained from satellite (gridded data) or from rain-gauge stations (scattered data). In the second case, a process of interpolation is needed to associate the rain amount to each point of the DEM. In this study rain-gauges recordings are used: from this data the natural neighbor interpolation is performed to obtain values over the entire area. A generalized view of the maps, containing the above-mentioned properties, is shown in Fig. 5. Concerning the soil properties, these are obtained from the lithology classes contained in Fig. 5e. Furthermore, a single rainfall map is shown, referred to the peak hour interval (2 hours before the estimated landslide occurrence).

b

a

c

d

e

f

Fig. 5. (a) Orthophoto; (b) Elevation; (c) Slope angle; (d) Aspect angle; (e) Lithology classes; (f) 1h rainfall 19:00-20:00 02-02-2014.