Predicting Rainfall-induced Movements of Slides in Stiff Clays

A physically-based numerical method is presented for displacements hazard analyses, at large-scale, in the case of landslides characterized by movements along pre-existing slip surfaces induced by rainfall-triggered pore pressure fluctuations. The method comprises a transient seepage finite element analysis and a kinematic model. With reference to the latter, the rates of displacement are assumed to be of the viscous type and are related to the factors of safety along the slip surface computed performing time-dependent limit equilibrium analyses. Monitoring data from an active slide in Central Italy are then used both for calibrating the models, by means of an inverse analysis procedure that minimizes the errors between numerically computed results and available observations, and for validating the results of the calibrated models. Subsequently, the calibrated and validated models are used to predict the response of the slope to different rainfall scenarios. The proposed method has been named “R-u-F-v prediction.

thickness of pyroclastic cover beds the case study of mount albino campania region southern italy

ABSTRACTThe paper presents a method for estimating and mapping – at detailed scale (1:5000) – the thickness of pyroclastic cover beds resting on calcareous bedrock. This method, tested in the study area of Mount Albino (Campania region, southern Italy), makes use mainly of information gathered from in situ investigations, managed and processed in a geographical information system environment via a geostatistical interpolation technique (i.e. ordinary kriging) and finally integrated and amended by adopting a heuristic approach. Given its easy applicability and affordable costs, the proposed method can be used in similar geological contexts where knowledge of the spatial distribution of pyroclastic cover beds is a requirement for understanding and predicting slope instability processes

A general framework and related procedures for multiscale analyses of DInSAR data in subsiding urban areas

In the last decade Differential Synthetic Aperture Radar (DInSAR) data were successfully tested in a number of case studies for the detection, mapping and monitoring of ground displacements associated with natural or anthropogenic phenomena. More recently, several national and regional projects all around the world provided rich data archives whose confident use, however, should rely on multidisciplinary experts in order to avoid misleading interpretations. To this aim, the present work first introduces a general framework for the use of DInSAR data; then, focusing on the analysis of subsidence phenomena and the related consequences to the exposed facilities, a set of original procedures is proposed. By drawing a multiscale approach the study highlights the different goals to be pursued at different scales of analysis via high/very high resolution SAR sensors and presents the results with reference to the case study of the Campania region (southern Italy) where widespread ground displacements occurred and damages of different severity were recorded

Comparison of Deaths Rates for COVID-19 across Europe During the First Wave of the COVID-19 Pandemic.

Background: Europe overall suffered greatly in the early stages of the COVID-19 pandemic but the impact of different countries varied. Italy was in the forefront, but there too there were differences, with the Lombardy region the epicentre of the pandemic. Methods: We report Crude Mortality Rates (CMRs) from deaths reported as due to COVID-19 and, in five countries where age-specific data are available, Standardized Mortality Rates (SMRs) in the European Union and United Kingdom. Results: As of 30th August 2020, Belgium was the country with the highest cumulative CMR (86.3/100,000), but the Lombardy region reached almost double this figure (167.6/100,000), far ahead of the corresponding figure for the rest of Italy at 37.0/100,000. SMRs could be calculated for five countries (Italy, Portugal, Sweden, Germany, and Netherlands). Among them, Sweden had the highest SMR (61.6/100,000). The corresponding figures for Italy, Netherlands, Portugal and Germany were 50.2, 41.4, 15.9, and 10.1 per 100,000, respectively. Conclusion: It is clear that countries within Europe have performed very differently in their responses to the COVID-19 pandemic, but the many limitations in the available data must be addressed before a definitive assessment of the reasons for these differences can be made

Recommendations for the quantitative analysis of landslide risk

This paper presents recommended methodologies for the quantitative analysis of landslide hazard, vulnerability and risk at different spatial scales (site-specific, local, regional and national), as well as for the verification and validation of the results. The methodologies described focus on the evaluation of the probabilities of occurrence of different landslide types with certain characteristics. Methods used to determine the spatial distribution of landslide intensity, the characterisation of the elements at risk, the assessment of the potential degree of damage and the quantification of the vulnerability of the elements at risk, and those used to perform the quantitative risk analysis are also described. The paper is intended for use by scientists and practising engineers, geologists and other landslide experts.JRC.H.5-Land Resources Managemen

Forecasting spring flow time series

The paper deals with a statistical analysis, carried out to define the underlying reason of some of the damage observed in many buildings of a southern Italian town. Engineering considerations, substantiated by specific measurements, attributed them to the lowering of the groundwater table in the area below the building locations. Due to two coinciding events which occurred in the preceding years, i.e. a persistent drought and the start up of a system of wells, it was not possible to define the cause of the former phenomenon. As shutting down the wells could generate additional problems, an accurate picture of the whole situation was necessary, before taking any action. By taking advantage of some fragmentary databelonging to the flow of a spring located in the area and on the basis of the knowledge of the rainfall data recorded in the Italian hydrographic service directory, two models have been developed which reproduce the spring flow time series in relation to the rainfall recorded in the surrounding area. By comparing the spring flow predictions with the actual data it has been possible to highlight the main role played by the wells

Problematiche connesse con la definizione del rischio da frana in aree di rilevante estensione.

Incontro Annuale dei Ricercatori di Geotecnica - IARG 2003, Potenz

Criteri di analisi e gestione del rischio da frana: dal Governo centrale alle comunità locali

L’analisi e la gestione del rischio da frana hanno fatto registrare una significativa accelerazione in Italia a partire dal maggio 1998, quando il Dipartimento della Protezione Civile nazionale decise di gestire secondo canoni avanzati l’emergenza causata dalle colate rapide di fango che avevano funestato cinque Comuni della Regione Campania. In virtù dell’esperienza maturata nel corso di questa emergenza, e grazie ai dispositivi legislativi emanati nei mesi successivi, il nostro Paese si dotò, infatti, di una zonazione del rischio da frana sull’intero territorio nazionale che, ancora oggi, costituisce uno strumento di gestione di grande rilievo in ambito nazionale ed internazionale. Partendo da questo patrimonio di conoscenze, la relazione mostra preliminarmente le modalità con le quali sviluppare un’analisi ed una gestione del rischio ancora più avanzata, oltre che integrata tra le principali Autorità competenti in materia di difesa del suolo, e si sofferma poi sugli aspetti economici e legislativi dai quali non si può prescindere laddove si voglia perseguire una mitigazione del rischio realmente efficace oltre che sostenibile per la Società

The influence of grass roots on the shear strength of pyroclastic soils

The paper investigates the effects of indigenous vegetation on the shear strength of loose pyroclastic soils of the Campania region (Southern Italy); these soils are frequently affected by shallow landslides 1-2m deep that experience static liquefaction during the post-failure stage. Perennial graminae grasses were seeded in a 1D column 2 m high and filled by pyroclastic soils, allowing the root to grow under atmospheric conditions. A noninvasive sampling procedure was adopted to take the vegetated soil samples, in which the roots were in their natural geometrical distribution. For each rooted sample, the root biomass RM was measured, and the root volume density RVD was calculated. Isotropic consolidated triaxial tests in both drained and undrained conditions were performed on the rooted specimens, as well as on bare specimens as a control. The obtained results showed that the roots generally provided an increment to the soil strength. In drained conditions a reduction in the volumetric deformation was observed, which, under undrained conditions, was reflected in a general reduction of the excess pore water pressures with a possible inhibition of the static liquefaction occurrence. This study highlights the potential role of grass roots as bio-engineering practice for stabilizing shallow covers of pyroclastic soils.The influence of grass roots on the shear strength of pyroclastic soilsacceptedVersio