Analysis of Snowmelt as a Triggering Factor for Shallow Landslide

Abstract

Shallow landslides are induced by extreme hydrological events or by events of medium intensity but prolonged over time. Such slips involve generally limited portions of land; however, they are dangerous due to the absence of warning signals and the lack of knowledge regarding their possible evolution. The aim of this paper is to study the evolution of shallow landslides affected by snowmelt and rainfall and to compare the observations done in situ by means of a statistical analysis of meteorological variables with those made in the laboratory. Few authors have addressed the role of snow to slope instabilities, nevertheless, in the context of ongoing climate change, the study of glacier and snow melt must be further explored. For this reason, this work deals with the study of in situ seasonal processes observed at a mountain closed basin nearby Champoluc in Aosta Valley region. To understand and to improve triggering threshold in snowy region, snowmelt and meteorological analyses were carried out by means of a cutting-edge weather and snowpack station. All the available data have been examined with a series of statistical analysis to define snow melting trends in relation to meteorological conditions. After that, some tests were performed at GAP2 Lecco laboratory taking into account the onsite observations to evaluate the consequence of studied atmospheric conditions on a downscaled reproduced slope covered by snow. Therefore, it was possible to observe the direct interaction between soil and snow and how infiltration process takes place under settled conditions.

Application of Lucas-Kanade Dense Flow for Terrain Motion in Landslide Monitoring Application

“…As in (Ivanov et al, 2020, Ivanov et al, 2021, Panzeri et al, 2022, the landslide bodies of the present work experiments were both composed of homogeneous medium sand (d50 = 0.35 mm, uniformity coefficient Cu = 1.75, internal friction ϕ = 34°). The sand was disposed in the flume in three steps, laying and compacting three subsequent sand layers in order to achieve a uniform compaction for a total thickness of 15 cm.…”

“…On the other hand, tensiometers measure pressure [kPa] and temperature [°C]. In order to evaluate soil suction, porous heads full of water were installed on the tensiometers, therefore the pressure measured by the tensiometers was the negative pressure of water flowing out of the porous heads and soil saturation is reached when the measured value is zero (Kandelous et al, 2015, Wu et al, 2015, Panzeri et al, 2022. As regards the ERT profiles, the measurements taken every 3-4 minutes show the variation of soil resistivity, which is related to the increase/decrease of water content (Hojat et al, 2019, Ivanov et al, 2020.…”

Geotechnical and Geophysical Assessment of the 2021 Tamban Chimbo Landslide, Northern Andes of Ecuador

“…There are certainly further examples of integrations between different approaches, methods, and techniques in obtaining data, such as studies of the evolution of shallow landslides affected by rainfall, which are compared with the observations realized in situ by means of a statistical analysis of meteorological variables with those obtained in the laboratory [1,24,25]. Furthermore, a combination of geophysical methods have been used for the characterization of a rockslide area, where the results have been calibrated by comparing the geophysical responses with the geological evidence derived from boreholes and with the movements recorded using an inclinometric probe [25].…”

“…Worldwide, massive mass movements such as landslides or rock falls and avalanches are predominantly the result of the combined action of the earth's internal and external forces, environmental factors, and inadequate human engineering activities [1][2][3][4][5][6][7][8]. Similar to other equivalent orogenic settings throughout the globe, in the northern Andes of Ecuador, landslides are the most recurrent natural phenomena in mountainous areas, where lithological, seismic, and geomorphological as well as climatic factors play an important role in their dimension and classification, whether they are coherent, disruptive, or lateral spreads [9][10][11][12].…”