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Excess pore-water pressure development during installation of piles into saturated clays is of primary importance and strongly affects pile bearing capacity and settlements. Such a problem is well known in literature, but excess pore-water pressure magnitude prediction, and then that of the bearing capacity, is an open research topic. In addition, excess pore-water pressure may increase greatly when numerous piles are installed in a relatively small area - as in the case of a pile group foundation - thus leading to a non-negligible modification of stress conditions at the soil-pile interface and, as a consequence, to a temporary reduction of ultimate load-bearing capacity. The paper focuses on the interpretation of load-test data performed on several auger-screw piles (full displacement), part of an important soil improvement intervention in Parma (Italy). The analysis of load test showed low values of ultimate load bearing capacity of the tested piles. Hence, the need to investigate the evolution of excess pore-water pressure with time and its relationship with the ultimate pile bearing capacity. In addition, special attention is dedicated to the study of possible mechanisms standing beneath the superposition of excess pore-water pressure effects among adjacent piles. Eventually, in order to give a consistent theoretical explanation of the recorded data, a simplified model is introduced. Such a model could be applied to similar case studies.

The reliability of river embankments is essential for flood risk management. The Po River, which flows through the North of Italy, is safeguarded over half of its length by major river embankments. Performance assessment of such water-retaining structures has become a major concern following some significant flood events in the past. Among the possible initiating causes of failure, backward erosion piping turns out to be particularly threating in the middle-lower stretch of the river. In particular, the November 2014 high-water event triggered the formation or reactivation of a few important sand boils. The paper presents a preliminary 3D finite element model of the groundwater flow through a selected cross section of the Po river, located in the Province of Reggio Emilia, which experienced a reactivation of piping phenomena after the 2014 event. The numerical model, based on a detailed geotechnical characterization obtained from in situ tests, was calibrated on the basis of the 2014 high-water event measurements and verified for a subsequent event that took place in November 2016, though without any relevant sand boil reactivation. Results are discussed with the aim of providing some insight into the mechanism under study.

L’articolo descrive uno studio riguardante i fenomeni deformativi osservati dopo il sisma dell’Emilia del maggio 2012 lungo un tratto di argine del Canale Diversivo di Burana che ricade nell’abitato di Scortichino, frazione del comune di Bondeno (FE). In questa porzione del rilevato arginale sono state edificate oltre un centinaio di abitazioni ed alcune strutture di medio-piccole dimensioni adibite ad attività produttive o a deposito, molte delle quali sono risultate pesantemente danneggiate e dichiarate inagibili proprio a causa delle deformazioni e del sistema di fratture longitudinali presenti nel terreno in seguito al terremoto. Il contributo qui presentato si prefigge di analizzare la risposta sismica dell’argine durante la sequenza sismica del 2012, comprendere le cause dei dissesti nonché individuare le necessarie azioni di mitigazione e gli eventuali interventi di messa in sicurezza nei confronti di terremoti futuri. A questo scopo è stata condotta un’ampia campagna sperimentale di indagini in sito e in laboratorio, finalizzata alla ricostruzione di un accurato modello geotecnico per la valutazione delle condizioni di stabilità dell’argine in condizioni sismiche, portando in conto anche l’eventuale insorgenza di fenomeni di liquefazione nei terreni sabbiosi superficiali costituenti la fondazione del corpo arginale. L’analisi illustrata è il risultato dell’attività di indagine svolta per più di un anno dal Gruppo di Lavoro Argini (GdLA), costituitosi nel luglio 2012 in seguito ad un accordo fra la Regione Emilia-Romagna e l’Associazione Geotecnica Italiana per la verifica delle condizioni di stabilità dei rilevati arginali nelle aree colpite dal terremoto.

The seismic sequence that in May 2012 struck a large area of the river Po Valley (Emilia-Romagna region, Northern Italy) triggered significant fractures and deformations in a number of riverbanks located close to the earthquake epicenter. Among them, one of the most severely damaged structures turned out to be the banks of an irrigation canal known as Canale Diversivo di Burana, flowing through the small village of Scortichino (Municipality of Bondeno), near the historic town of Ferrara. Large, longitudinally-oriented ground cracks were observed along a 3 km bank stretch, causing in turn severe structural damages to a large part of the approximately one hundred houses and productive activities built on the bank crown. In order to interpret the response of such soil structure during the 2012 earthquake by identifying possible damage causes as well as to suggest relevant remedial measures and seismic risk mitigation actions towards possible future earthquakes, the Emilia-Romagna regional authority launched an in-depth study carried out by a number of research groups from various Italian universities in cooperation with technical experts of the Geological, Seismic and Soil Survey Regional Department. To this purpose, a number of geotechnical investigations were performed (in situ and laboratory tests) and an accurate geotechnical model for the seismic stability analyses was thus defined. Potential liquefaction phenomena of the shallow sandy soils, in the foundation subsoil, were taken into account in the analyses. The paper describes the main features of the extensive study carried out by the working group and summarizes the most significant achievements of the analyses.

Since approximately 75% of Europeans currently live in cities, and this number will rise, urban areas are the most important testbeds for energy transition, climate change adaptation measures, and decarbonisation models, on which studies and efforts for concrete change must focus. The teaching of mitigation and adaptation measures to climate change and decarbonisation models has gradually taken up space within university courses. However, the complexity of the decarbonisation issue is raising awareness on the urgency of an interdisciplinary approach that can be conveyed by spatial planning. Currently, this approach is not widespread in Higher Education Institutions in Europe but is nonetheless necessary to let new professional profiles emerge who are able to coordinate different stakeholders, data, and information sources. The Erasmus+ project CITY MINDED (2020–2022) has worked in this direction, by developing and testing a methodology for the design of a structured ordinary practice for teaching urban decarbonisation to students in Higher Education. This practice (at the same time, interdisciplinary, collaborative, experiential, and place-based) aims to offer students a combination of different approaches and working methods to investigate and improve urban neighbourhoods and districts, resulting in the definition of an operative roadmap for decarbonisation in the medium-to-long-term. The aim of this article is to highlight the learning-by-doing experience developed by the project consortium, with reference to the testing of the methodology conducted within an Intensive Course in the City of Valletta (Malta). In particular, the paper illustrates how this experience succeeded in stimulating students with different academic backgrounds to establish connections across disciplines, in raising their awareness about the complexity of city decarbonisation processes. Overcoming the strict time and budget constraints of an EU-funded project, such an approach can be further developed, replicated on theoretical grounds, and implemented within different degree programmes dealing with urban sustainability.

The Po River (Northern Italy) is the longest watercourse in Italy and over half of its length is safeguarded by major river embankments. Their stability is crucial for the local communities, being the Po River plain densely populated. Among all possible failure mechanisms, backward erosion piping at the interface between the bottom sandy aquifer and the overlying fine-grained soils has proved to be one of the most threatened phenomena. This paper describes the reactivation of a sand boil in a river embankment section in the Province of Ferrara, during the 2014 major high-water event. Detailed stratigraphic soil profiling as well as careful geotechnical characterization of the embankment and of the subsoil have been carried out on the basis of in-situ tests. Then, safety assessment of the backward erosion piping has been performed using simplified prediction tools and a preliminary 2D numerical model. Results are compared and discussed with the aim of providing some insight into the mechanism under investigation.

A recent study (Aielli et al. 2017) about sand boil reactivations in the major Po river banks (Italy) has demonstrated how a structured database of historic information can significantly contribute to better understanding of seepage phenomena and provide a practical tool for safe management of hydraulic works. The primary aim of the present work is to enhance the information collected in the database (DB), which cover the whole course the Po river, to the beginning of the delta. In particular, an improved estimation of the critical height (i.e. height of the water level in the river which causes a sand boil reactivation) for sand boil phenomena is discussed herein. The maximum height without reactivation and the minimum height with reactivation have been evaluated for each recorded sand boil. The DB information and processing of the available data allow defining how the values of the critical heights are distributed along the course of the river. The DB information, connected to the alert thresholds and to the early warning system, can provide an indication of the possible reactivations of the piping phenomena in advance, enabling efficient coordination of the emergency actions against backward erosion piping progression.