Physically based approaches incorporating evaporation for early warning predictions of rainfall-induced landslides

Abstract. In the field of rainfall-induced landslides on sloping covers, models for early warning predictions require an adequate trade-off between two aspects: prediction accuracy and timeliness. When a cover's initial hydrological state is a determining factor in triggering landslides, taking evaporative losses into account (or not) could significantly affect both aspects. This study evaluates the performance of three physically based predictive models, converting precipitation and evaporative fluxes into hydrological variables useful in assessing slope safety conditions. Two of the models incorporate evaporation, with one representing evaporation as both a boundary and internal phenomenon, and the other only a boundary phenomenon. The third model totally disregards evaporation. Model performances are assessed by analysing a well-documented case study involving a 2 m thick sloping volcanic cover. The large amount of monitoring data collected for the soil involved in the case study, reconstituted in a suitably equipped lysimeter, makes it possible to propose procedures for calibrating and validating the parameters of the models. All predictions indicate a hydrological singularity at the landslide time (alarm). A comparison of the models' predictions also indicates that the greater the complexity and completeness of the model, the lower the number of predicted hydrological singularities when no landslides occur (false alarms)

Two Applications of Soil Water Balance in Unsaturated Pyroclastic Soils

Abstract Evaluation of the monthly soil water balance (SWB) provides a tool for understanding and predicting the effects of seasonal and long-term changes in soil water conditions within many geotechnical problems. In this paper, two applications of the SWB approach in the pyroclastic partially saturated soils are shown. Firstly, rainfall, evapotranspiration, water storage measured or estimated at the experimental site in Monteforte Irpino (in Southern Italy) are shown. Secondly, rainfall, infiltration, actual evapotranspiration and water storage measured by data provided by a physical model are shown. In the both cases, data are reported over two years (2010-2012). The physical model was constituted by a wooden tank filled with reconstituted silty pyroclastic soil taken from experimental site at Monteforte Irpino (AV) and it was exposed to the atmosphere at a site in Napoli. Comparison between soil hydraulic behaviours observed is discussed and the scale effects on the estimation of the SWB are analysed, treating with practical implications. From the results, it is clear that similar trends in SWB and the same value of suction over wet season (10 kPa) can be observed at both the scales in spite of differences in meteorological conditions and hydraulic properties of soils exposed to atmosphere

Comparing Different Modelling Strategies for the Estimation of Climate Change Effects on Urban Pluvial Flooding

In this paper, two different strategies are presented that allow for the assessment of the effects of climate change on urban pluvial flooding, in order to understand potentialities and limitations, advantages and drawbacks. The two strategies are hereby defined as “top-down” and “bottom-up”, according to the relative position of climate change modelling with respect to flood modelling (upstream for top-down, downstream for bottom-up). To provide a practical example, the two strategies are applied to a case study located in Naples, Italy. However, they can be successfully extended for the assessment of any potential impact of climate change in any location

Analisi dei cinematismi post rottura meteo-indotti in un rilevato stradale fondato su un versante marnoso

Un tratto di rilevato dell’Autostrada A24 Roma-L’Aquila-Teramo, realizzato lungo una porzione della dorsale appenninica laziale posta tra i comuni di Roviano (RM) ed Arsoli (RM), è stato interessato a partire dalla fine degli anni ‘80 da continui fenomeni di avvallamento. I dati inclinometrici a disposizione hanno evidenziato che tali dissesti sono il risultato di un meccanismo di rottura che ha interessato non solo il rilevato ma anche il versante marnoso-arenaceo su cui esso è fondato. Avendo il monitoraggio messo in luce una variabilità stagionale delle velocità di spostamento, è stato sviluppato un modello semplificato finalizzato a ricostruire la cinematica meteo-indotta del fenomeno portando in conto le forzanti atmosferiche che regolano il processo. La nota descrive i principali risultati di tali analisi

Thermal design of structures and the changing climate

The report presents the work of the Joint Research Centre’s scientific network on adaptation of structural design to climate change focusing on the thermal design of buildings and infrastructure considering the changing climate. It presents scientific and technical background intended to stimulate debate and serve as a basis for further work to study the implications of climate change on the thermal design of structures. The report first outlines recent EU policies in support of sustainability and climate resilience of infrastructure and buildings. It highlights how the construction sector is encouraged to adopt more sustainable and circular economy practices, extend the lifetime of buildings and strive for better performance of buildings and infrastructure throughout their life cycle. It further emphasises the ongoing action plan to adapt the European standards to a changing climate. Following, the report explains the concept of the definition of thermal actions for the design of buildings and infrastructure using the European standards for structural design, i.e. the Eurocodes. It is showed that the adaptation of structural design to the implications of climate change is strongly linked with the assessment of changing characteristics of climatic actions (including thermal ones) in terms of the Eurocodes concept for the variable climatic actions. Variations in temperature that would directly affect the design values for thermal actions in the European standards are studied in depth for the case study of Italy. It is concluded that an increase in the maximum and minimum temperature used for structural design is expected all over Italy. It is discussed that structures, as bridges for example, are expected to be influenced by stresses from extreme temperatures and thus, should be designed for temperature amplitudes justified from climate projections for the actual region. However, the current European maps for thermal design are based on climatic data which, with some exceptions, are mostly 10 to 15 years old and ignore the potential effects of climate change. Thus, new European maps for the thermal design of structures should be developed using data that project more realistically the future climate. To this end, the authors present a methodology for developing thermal maps for structural design taking into account the influence of the changing climate and present an implementation of the methodology using the example of Italy.JRC.E.4-Safety and Security of Building

Expected implications of climate change on the corrosion of structures

The report presents the work of the Joint Research Centre (JRC) scientific network on adaptation of structural design to climate change addressing the expected implications of a changing climate on the corrosion of structures. The work first outlines recent EU policies supporting the sustainability and climate resilience of infrastructure and buildings. It is highlighted how the construction sector is encouraged to adopt more sustainable and circular economic practices, extend the lifetime of buildings and strive for better performance of buildings and infrastructure throughout their life cycle. The ongoing action plan to adapt European standards to a changing climate is emphasised. The report evaluates the expected variations in climatic factors causing corrosion, provides a state-of-the-art review on climate change induced corrosion of reinforced concrete and steel structures, and presents recent works on the corrosion impact, the costs and effectiveness of adaptation strategies. The effects of corrosion on the seismic performance of structures is addressed as well. In conclusion, this report presents the scientific and technical background to study the expected implications of climate change on the corrosion of structures. The work intends to stimulate debate on the subject, identify further research needs, and serve as a basis for the development of further work relevant to the adaptation to climate change of European standards and policies.JRC.E.4-Safety and Security of Building

Evaluation of Variations in Frequency of Landslide Events Affecting Pyroclastic Covers in Campania Region under the Effect of Climate Changes

In recent years, pyroclastic covers mantling slopes in the Campania region of southern Italy have frequently been affected by flowslides. Due to high exposure and demographic pressure in these areas, assessment of the potential effects of climate change on the frequency of such events has become a crucial issue. In this regard, our paper proposes a simulation chain comprising three main elements: (i) climate simulation at the highest horizontal resolution available for Italy (8 km); (ii) a bias correction procedure in an attempt to remove systematic errors in the entire weather forcing probability distribution; (iii) the data obtained used as input for an interpretative tool estimating the evolution of soil pore water pressure and water storage (bulk water content) by means of a well-calibrated coupled thermo-hydraulic approach able to adequately take into account soil-atmosphere interaction dynamics. The predictive ability of the geotechnical model to reproduce failure conditions was tested by forcing it with temperature and precipitation observations. Subsequently, the performance of the entire modeling chain was evaluated for a period from 1981 to 2010. Lastly, variations in landslide occurrence were assessed up to 2100 under two concentration scenarios. An increase with different features was estimated under both scenarios depending on the time horizon and the severity of the concentration scenario

Sistemi di allarme per colate rapide in terreni piroclastici: elaborazione di modelli previsionali

La tesi elabora alcuni approcci originali per la previsione tempestiva di colate rapide di fango, da utilizzarsi all'interno di sistemi di allarme finalizzati alla riduzione del rischio. Il lavoro inquadra dapprima il problema, descrivendo le principali case-histories che la letteratura consegna sul tema. Quindi illustra gli approcci matematici idonei a simulare l'interazione tra suolo ed atmosfera. Descrive quindi un'attrezzatura sperimentale progettata e realizzata per studiare in condizioni sufficientemente controllate l'interazione tra suolo ed atmosfera e per ricavare i parametri dei modelli prescelti. Infine vengono proposti due approcci per la previsione tempestiva dei sistemi di allarme. Entrambi sono verificati attraverso l'interpretazione della case-history meglio documentata, la case-history di Nocera Inferiore 2005