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Dataset on the bearing capacity of curved profiles obtained by roll forming process
Get PDFThe paper shows experimental data concerning the bearing capacity of curved profile sheets achieved by roll forming process.
Two different restraint configurations were considered, respectively named A and B and representing the only bending and the axial-bending conditions. Two different experimental setup, i.e. single span with and without horizontal restraints were adopted. Trapezoidal and sinusoidal steel sheets with variable thickness and curvature radius were tested. Setup configurations, collapse
mechanisms and load-deflection diagrams are presented
Knowledge-Based Approach for the Structural Assessment of Monumental Buildings: Application to Case Studies
Get PDFHistorical buildings are characterized by a high level of complexity due to a long realization process often resulting in an overall lack of information and in a structural behavior that is more similar to a “structural aggregate” rather than to a “single building”. The assessment of the static safety and seismic vulnerability then requires a multidisciplinary and multilevel approach including a deep and accurate preliminary knowledge phase before performing structural analyses. In the present paper, a consolidated knowledge-based procedure is presented and applied to four case studies in Italy. Interest is focused on the knowledge phase, combining critical–historical analysis to in situ architectural, geometrical, structural, material, and geotechnical aspects. The knowledge phase proves to be fundamental in understanding the structural behavior of cultural heritage, with special attention to the determination and analysis of local mechanisms and vulnerability elements and allowing to validate and give reason to numerical results
Simplified approaches for the analysis of historical monumental masonry buildings: the case study of the Certosa di Calci
No full textThe historical monumental masonry buildings play a fundamental role in the World Cultural Heritage, especially in the European country. They are generally characterised by a limited initial knowledge (e.g. geometrical, structural and historical features), by large dimensions and great structural complexity and heterogeneity. The structural complexity is a natural consequence of a usually long constructive genesis characterised by additions, transformations and demolitions realised during centuries, determining a great heterogeneity in the geometrical-structural features and widespread irregularities. Further, the constructive phases are not properly documented (or not documented) since they are often a consequence of practical needs and not of systematic planning, making it hard to comprehend the morphological evolution. Besides being difficult to reconstruct through the only historical analysis commonly adopted for ‘ordinary’ historical buildings, such an intricate construction process determines a structural behaviour similar to structural aggregate, composed of several Structural Units (SU), more than to single building. Therefore, the procedures commonly adopted for the structural evaluation of ordinary buildings are often partially ineffective if applied to the present building typology, or extremely demanding in time and economic resources.
The scientific literature currently faces the theme of the analysis of historical buildings according to different ‘scales’ and several procedures; however, a complete methodology properly calibrated and accounting for all the peculiarities of monumental buildings is still missing. The present thesis has been developed to analyse the behaviour and the specific features of this building typology and propose a proper methodology for the investigation and the structural assessment finalised to the possible planning of retrofitting interventions. A multi-step multidisciplinary procedure, characterised by a progressive increase of the knowledge level and analysis detail, was elaborated and tested on a representative case study: the Certosa di Calci monumental building near Pisa (Italy).
The first fundamental step of the proposed procedure consisted of multidisciplinary and integrated knowledge analysis, comprehensive of the contribution of more fields – e.g. historical-critical analysis, geometrical and structural survey, in situ investigations – essential to determine a sort of ‘state of the art’ of such complex buildings. Regarding the Certosa di Calci, different sources’ contributions – e.g. archival documents, iconographic sources, bibliographic references, geometrical/architectural/structural issues – were compared and elaborated in a synergic and iterative process. The final aims were to reconstruct the morphological evolution, comprehend the aggregate’s inner behaviour, and identify the SUs within the monumental complex. Different disaggregation criteria were accounted, looking for a compromise between homogeneity of the inner geometrical and structural features and reliability of the structural behaviour.
The subdivision of a monumental building into its SUs allowed to approach it as an urban aggregate, resorting to the macroseismic risk analysis commonly adopted for large-scale evaluations. A procedure and a specific survey and evaluation form were elaborated, based on the scientific literature's approaches for other building typologies, properly modified to fit the considered case. An index risk was achieved for each SU through the proposed form, consequently determining a sort of ‘priority list’ within the aggregate, allowing identifying the areas to be more urgently in depth-analysed to design retrofit interventions.
According to the progressive deepening line, the following step in the procedure was to execute numerical analyses useful to detail the in-aggregate behaviour and the phenomena related to the units’ interaction according to some recurrent aggregation cases. Finite Element Method models of some representative SUs were defined, adopting some necessary simplifications, and preliminarily validated through linear analyses. Later, nonlinear static analyses were performed to investigate the structural behaviour of the SUs both as single buildings and as aggregates according to different configurations, analysing the interaction phenomena and their influence over the global capacity.
Finally, the work focused on developing a simplified numerical model to simulate the in-aggregate behaviour once knowing the complex FEM models' result. A proper investigation of the stresses transferred through the contact area between two adjacent SUs was performed. It was needed to propose a reliable simplified approach based on the detailed numerical model of a unit and the simulation of the interaction with the adjacent ones through a set of nodes and springs. The influence of parameters such the mass and stiffness definition, and the connection among the numerical model and the simplified one were analysed, looking for a good compromise between result’s accuracy and speed in terms of model definition and analysis execution.
In conclusion, the methodology proposed allows a complete and coherent analysis of the structural capacity of a historical masonry monumental building, according to different detail levels and, consequently, different aims
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Tower Lanfreducci. Historical and architectural investigation finalized to the seismic structural analysis.
No full textLa tesi riguarda lo studio della torre Lanfreducci, sita a Pisa e avente origine medievale. L'analisi della struttura è stata svolta su più fronti e comprende aspetti storici, architettonici e strutturali.
E' condotta un'indagine volta a comprendere le origini della torre, il suo rapporto con la struttura urbana di Pisa nel corso dei secoli e gli eventi storici che l'hanno riguardata più da vicino contribuendo a modificarne l'aspetto. E' stato eseguito il rilievo geometrico e un'analisi dei materiali al fine di una più completa conoscenza dell'edificio e della sua evoluzione storica. Infine è stata svolta un'analisi strutturale comprendente di una fase di modellazione agli elementi finiti, una fase di calibrazione e un'analisi pushover finalizzata alla valutazione del comportamento sismico della torre
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Analisi macrosismica del Complesso Monumentale della Certosa di Calci
No full textIl progetto tratta dell'elaborazione e la successiva applicazione di una scheda di valutazione macrosismica al complesso della Certosa di Calci.
A partire dai contributi presenti in letteratura, in particolare dalla metodologia GNDT di primo livello, è stata elaborata una scheda di valutazione macrosismica che tiene conto delle caratteristiche tipologiche, strutturali, dello stato di conservazione e delle vulnerabilità/ criticità presenti nel manufatto architettonico, nonché – seppure in maniera semplificata – dell’esposizione e della pericolosità.
In seguito a un rilievo tipologico e una analisi del quadro fessurativo della struttura è stata compilata la scheda per il complesso in esame e successivamente assegnato un punteggio e un corrispondente peso alle varie informazioni raccolte. Tutto per arrivare a una classificazione macrosismica, assegnando un indice di rischio tale da consentire un rapido confronto tra le diverse porzioni analizzate.
The project deals with the elaboration and subsequent application of a macroseismic evaluation form to the complex of the Certosa di Calci.
Starting from the contributions in the literature, in particular from the first level GNDT methodology, a macroseismic evaluation form has been prepared which takes into account the typological characteristics, controlled, the state of conservation and the vulnerabilities / criticalities present in the structured building, as well as - albeit in a simplified way - exposure and danger.
Following a typological survey and an analysis of the crack pattern of the structure, the form was compiled for the complex in question and assigned a score and a weight corresponding to the various information collected. All to arrive at a macroseismic classification, assigning a risk index to allow a rapid comparison between the different portions analyzed
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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