SCC, FRP, incamiciatura, per un intervento di rinforzo di strutture in c.a. fortemente degradate del dopoguerra

L’articolo espone problematiche palesatesi e rimedi adottati nel particolarissimo ed emblematico caso studio di un fabbricato sito in Napoli, edificato nell’immediato dopoguerra (1947/49), e che nel 2011 ha presentato gravi problemi agli elementi strutturali in calcestruzzo armato. Grazie ad una estesissima campagna di prove in sito, si è potuto innanzi tutto valutare la legge di variabilità dei fenomeni degradanti in funzione del fronte di esposizione e dell’altezza, e quindi si è potuto concepire un intervento di rinforzo, dalle fondazioni fino al piano attico, attuato con materiali di ultima generazione (calcestruzzo autocompattante, materiali compositi), e tale da garantire un nuovo ciclo di vita superiore a quello da considerare ormai concluso. Dal punto di vista sperimentale, a tal fine, sono stati in parallelo condotti studi finalizzati alla determinazione del momento nel quale la carbonatazione avrà superato il guscio di rivestimento in SCC, e riproporrà quindi il problema dell’aggressione al calcestruzzo di origine. Sulla base di sperimentazioni condotte mediante test di carbonatazione accelerata secondo la norma UNI EN 13295-2, dei modelli teorici della letteratura internazionale sull’argomento ma anche dei dati raccolti sul campo, è stato ipotizzato – con riferimento al noto modello di Tuutti – il periodo di ultimazione dell’innesco e di inizio della propagazione. Il caso può essere considerato, per questo tipo di edifici, paradigmatico per valutazioni di resilienza del patrimonio edilizio nonché per strategie di riduzione di vulnerabilità, sia per la fase di approccio (diagnosi ed intervento) sia per la fase di programmazione della manutenzione, alla luce del fatto che in Italia circa il 70% degli edifici sono stati costruiti dopo il 1946 e quasi tutti hanno le stesse caratteristiche costruttive, mentre circa il 30% è stato edificato fra il 1946 ed il 1971 (anno di pubblicazione della legge 1086), e buona parte di essi è prevedibile possano avere problematiche analoghe nei prossimi anni

Development of a new GIS-based method to detect high natural value farmlands. A case study in central Italy

An original method for the identification of High Natural Value farmlands is presented. Gathering information about land use (CORINE Land Cover), geomorphology (elevation and Terrain Ruggedness Index) and remote sensing data in a GIS environment we were able to develop a new detection process; its application to a wide sector of central Italy, in areas characterized by high biodiversity and relevant agronomic and cultural value, is presented. Thus, a new tool for diminishing sampling efforts and economic and time wastes in territorial studies is provided

Mortars with Recycled Aggregates from Building-Related Processes: A ‘Four-Step’ Methodological Proposal for a Review

Because the production of aggregates for mortar and concrete is no longer sustainable, many attempts have been made to replace natural aggregates (NA) with recycled aggregates (RA) sourced from factories, recycling centers, and human activities such as construction and demolition works (C&D). This article reviews papers concerning mortars with fine RA from C&D debris, and from the by-products of the manufacturing and recycling processes of building materials. A fourstep methodology based on searching, screening, clustering, and summarizing was proposed. The clustering variables were the type of aggregate, mix design parameters, tested properties, patents, and availability on the market. The number and the type of the clustering variables of each paper were analysed and compared. The results showed that the mortars were mainly characterized through their physical and mechanical properties, whereas few durability and thermal analyses were carried out. Moreover, few fine RA were sourced from the production waste of construction materials. Finally, there were no patents or products available on the market. The outcomes presented in this paper underlined the research trends that are useful to improve the knowledge on the suitability of fine RA from building-related processes in mortars

Caratteristiche e durabilità delle malte con materiali riciclati

Molti studi sono stati condotti negli ultimi anni sull’utilizzo di materiali di risulta per il confezionamento di malte, probabilmente a seguito di una mutata coscienza in tema di sostenibilità. I risultati sono stati in genere interessanti, e hanno evidenziato la possibilità di ottenere prodotti caratterizzati da prestazioni, di vario tipo, soddisfacenti. Una recente sperimentazione condotta presso i laboratori dell’Università Politecnica di Madrid, in collaborazione con l’Università di Napoli Federico II, ha indagato su una vasta gamma di prodotti con utilizzo di materiali da riciclo, offrendo così numerosi spunti per l’utilizzo di malte a base di cemento con inerti provenienti da rifiuti, anche in combinazione con inerti naturali. Alla luce dei risultati, tuttavia, emerge la necessità, per identificare la migliore combinazione fra tutte quelle possibili, di individuare preliminarmente lo specifico utilizzo della malta da produrre, così da finalizzare lo studio sia in termini di prestazioni che in termini economici, Di particolare rilevanza, poi, appare il problema della durabilità, soprattutto per alcuni degli utilizzi, ovvero quelli che vedono la malta maggiormente soggetta all’attacco degli agenti atmosferici

Modellazioni per il calcolo della vita utile di strutture in calcestruzzo armato

La vita utile degli elementi in calcestruzzo armato può essere calcolata, con buona approssimazione, mediante alcune metodologie, che consentono di prevedere sia il momento nel quale il fronte di carbonatazione avrà superato il copriferro e raggiunto le armature, sia la velocità con la quale la corrosione interesserà le armature, diminuendone la sezione. Una valutazione comparativa fra tre diversi tipi di edifici, realizzati con differenti calcestruzzi, evidenzia efficacemente quali possono essere gli scenari in termini di interventi manutentivi, e pone le basi per individuare le strategie più appropriate per il controllo dell’obsolescenza di queste strutture

Evolving Privacy Protections for Emerging Machine Learning Data Under Carpenter v. United States

The Fourth Amendment’s third-party doctrine eliminates an individual’s reasonable expectation of privacy in information they willingly turn over to third parties. Government scrutiny of this information is not considered a search under the Fourth Amendment and is therefore not given constitutional protections. In the 2018 case Carpenter v. United States, the Supreme Court created an exception to the third-party doctrine. In Carpenter, a case involving the warrantless use of cell site location information (CSLI) in a criminal investigation, the Court held that individuals do have a reasonable expectation of privacy regarding CSLI. According to Chief Justice Roberts, despite the necessary relinquishment of some information by all cell phone users, privacy is guaranteed “[i]n light of the deeply revealing nature of CSLI, its depth, breadth, and comprehensive reach, and the inescapable and automatic nature of its collection….” The Court’s rational in distinguishing CSLI is also applicable to the personal data that is constantly being collected by tech companies through the use of machine learning algorithms. Companies like Facebook and Google use machine learning to specifically tailor each user’s experience to their individual preferences. To do so, machine learning algorithms constantly collect, store, and analyze data about our interactions online to “learn” about our habits, ideologies, likes, dislikes, and affiliations. Given the Carpenter Court’s understanding of the constitutional complexities of high-tech communications, this comment takes the next step to explore individuals’ reasonable expectation of privacy in algorithmic learning data titrated to their personal preferences

A Model for Determining Accelerated Ageing Cycles in Durability Research: a Case study on Continuous Roofing

This paper introduces research about a model for determining the experimental ageing cycle in laboratory tests for evaluating durability. The model has been implemented with computer software that uses an algorithm in which the input is comprised of a series of climatic data that was obtained from various national climatic database sources. The model was implemented specifically for evaluating a continuous roofing sub-system, as part of a broader Italian national research project, related to the durability of building components. The Italian national research project has one that encompassed a network of research organisations from the Universities of Brescia, Catania, Milan, Naples, Palermo and Turin. Research on the durability of continuous roofing has typically been based on a comparison between the results from artificial ageing tests (conducted in a laboratory) with those obtained from natural weathering tests on the same sample. The approach taken in this research project was to attempt to simulate - in the laboratory - the environmental actions that roofing sub-systems are typically exposed to, in relation to the various climatic conditions in which they are expected to perform. The computer output derived from an application of the model provides for the duration of laboratory ageing sub cycles - each one representing, and essentially reproducing a climatic season - with respect to temperature, humidity, sunlight radiation, and rainfall to which the sample is subjected. In this way a “virtual year” is obtained comprising four climatic seasons, each having different values for temperature, humidity, sunlight radiation and rainfall. The values to consider in laboratory tests are those, for the region and the time of year, which represent the season in question. The necessary values for implementing the model proposed are fixed and given in the research for three particular contexts (Milan, Naples and Palermo) Actually, a method to compose the cycles test in any climatic context for various kinds of experimentation in laboratory about the simulation of environmental effects on each part of building has been already implemented

Application of FMEA method for assessment of reliability of structures

In the last years several methods have been proposed, aimed to explore the theme of degradation and reliability of building components, with the main purpose of preventing performance deficits in general, and especially from sudden and unforeseen faults. This topic is an element of strong competitiveness in the world of professionals and business, and fits with the trend clearly demonstrated by the regulatory framework, particularly in the field of structures. One of the methods that can be used to assess the suitability of a component to its performance specifications, and which belongs to the field of Risk Management, is FMEA, (Failure Modes and Effects Analysis). This methodology analyzes a project from the point of view of its reliability before it is carried out and realized.To allow this verification the components are firstly verified in the form of drawings, technical specifications, flow-charts, information, standards, etc. that are all the elements that make up the documentation of the work to be performed and the knowledge that is available on the subject. There have been many applications of FMEA on building components, and it is of particular interest - considering the recrudescence of seismic events of the last decade, but also the emergence of structural defects, even of a certain gravity – for the use in the field of structures. This is of a considerable relevance in a period when there are issues about the possibility of adaptation of the real estate to earthquakes, but it also raises the argument of the modalities and the criteria leading the inevitable reconstruction of what no longer exists. In this article an example of application to a reinforced concrete structure is shown, from which it is possible to notice the most critical items and the modalities for preventing negative events

Bleeding Green, White, and Red: The Relationship Between Separation and Assimilation, Trends in Italian American Political Radicalism, 1927-1969

This thesis explores the experiences of Italian American political radicals from 1927 to 1969, a time when Italians moved from the shadows and into the mainstream of American society. Through an analysis of the lives and actions of Italian American political radicals, I argue that these individuals included in this study utilized their sense if Italian heritage to varying extents in shaping the character of their radicalism. This thesis focuses on historical contexts that shaped their political radicalism. The individuals addressed actively engaged in political movements, participated in the labor force, ran for public office, and fought to protect their rights as citizens. During the 1920s and 1930s, these Italian American political radicals were mainly political refugees from Italy and predominantly worked as political organizers. By the 1940s and 1950 these political radicals were professional politicians and intellectuals. Finally, in the 1960s, intellectuals and student radicals of Italian American dissent come to the forefront of Italian American political radicalism. The paper also demonstrates that Italian American political dissent during the mid-twentieth century was not a threat to American society. Rather, during the period under consideration, Italian American political radicals aimed to both preserve and transform numerous aspects of American society that are considered to be fundamental and are widely accepted in the modern day. This thesis relies on a variety of sources ranging from oral history interviews from the Oral History of the American Left at Tamiment Library and Robert F. Wagner Labor Archives in New York, NY, dialog from the Congressional Record, personal manuscript collections, and historical newspaper articles