Validation and proposal of new rainfall thresholds for shallow landslide prediction in Posavsko hills, Eastern Slovenia

Abstract

Monitoring is important for assessing the stability of the ground and for confirming the validity of the design during the construction and operation of structures. The ideal monitoring system for projects in Rock and Geotechnical Engineering would be able to monitor the behavior of small to extensive areas continuously and automatically with high accuracy. In addition, the costs would be low and the system would be easy to handle. Satellite technology has the potential to realize the above monitoring system by combining it with conventional geotechnical instruments. In this paper, satellite technology for displacement monitoring, i.e., GPS and SAR, is firstly outlined and then the concept of spatiotemporal continuous displacement monitoring is introduced. The use of both satellite technology and geotechnical instruments is effective for geotechnical monitoring. Practical applications of GPS for landslide monitoring and collaborative researches using DInSAR with Balkan countries are described.

Determination of Empirical Rainfall Thresholds for Shallow Landslides in Slovenia Using an Automatic Tool

“…Overall, 67% of the considered landslides occurred in the areas of sedimentary rocks (bound and unbound), which take roughly half of the total territory of Slovenia (10,026 km 2 , 49.5%), while landslides in the area of limestones and dolomites (8803 km 2 , 43.4%) account for only 20% of the considered landslides. This proves the impact of lithology on landslide triggering conditions, as reported, e.g., by Jordanova et al [29], Peruccacci et al [39], Palladino et al [40], Vennari et al [50] and Gariano et al [51] Sedimentary rocks are relatively unstable masses that are very susceptible to weathering and consequently accumulate thick eluvium, which is the main source of material for shallow landslides. Figure 7a shows the ED conditions in each lithology class in log-log coordinates with the corresponding 5% NEP thresholds, T 5,IG , T 5,LD , T 5,US and T 5,BS (Table 1).…”

“…Bezak et al [27] determined empirical thresholds for flash floods and landslides in Slovenia using a copula-based method. Bezak et al [28] also worked on the application of hydrological modelling for temporal prediction of shallow landslides, while Jordanova et al [29] focused on the determination of empirical thresholds for shallow landslides in the Posavsko hills, Eastern Slovenia, with an analysis of antecedent rainfall and the intensity of seven major rainfall events between 2013 and 2017.…”

“…The system is based on the comparison between the forecasted precipitation for the next 24 h and rainfall thresholds, determined using the chi-square method and 40 years of average rainfall correlated to the lithological unit [1]. Recently, a validation of this LEWS was carried out [29,31] and demonstrated the need for new thresholds.…”