1,721,097 research outputs found
Materials and techniques of Art Nouveau architecture in Italy and Portugal: a first insight for an European route to consistent restoration
Full text linkThe results of the investigations on building materials and techniques of Casa Major Pessoa, a typical Art
Nouveau construction in Aveiro (Portugal), and two coeval Art Nouveau buildings in Bologna (Italy) are presented
as a methodological contribution to the restoration of this kind of buildings. This is the first step to
ascertain the existence of a common thread between local materials, technologies and architecture in European
countries at the same period. A holistic approach was adopted: materials were investigated along with
architectural, structural and technological features, in order to achieve a first insight into the Art Nouveau
architecture in Europe in particular for its consistent restoration without loss of historical memory
Development of a Decision Support System for the structural degradation analysis of RC buildings supported by user-reported data and modern Information Technologies
No full textExposure to aggressive environmental agents and aging can seriously harm reinforced concrete (RC) structures and affect the building’s service life. In particular, many buildings built during the extensive dissemination of RC construction technique present criticalities regarding performance and durability due to many issues: inadequate design of technical details, incorrect execution method, inadequate materials, improper maintenance or intrinsic limits and vulnerability of concrete.
Consequently, management and monitoring of existing buildings is a complex issue for holders and administrators that are responsible for the building operability and user safety. On the other hand, large-scale degradation analysis and maintenance procedures present critical points: i) non-uniform building knowledge, ii) need of performing several inspections, iii) complexity of the diagnostics related to the subjectivity of the surveyor, iv) vastness and deployment of buildings in the region. Such issues become particularly complex for public or private administrators, who usually have limited resources and often cannot rely methodologies and tools to face the problem. This thesis proposes an innovative approach for detecting building criticalities. In order to achieve the new system, four synergistically related methods are suitably developed and listed as follows: i) a novel DSS methodology for buildings’ assessment supported by modern Internet of Things tools (smart devices) and Information Technologies; ii) an innovative Optimized AHP (O-AHP) based on a Mathematical Programming problem; iii) a calibration procedure based on the Tuutti model to consider the damage evolution of reinforcements’ corrosion and tune the KPIs; iv) a Test Site involving 131 building on the Valencian coasts to test the DSS. In particular, the proposed DSS includes an innovative software application (APP) implemented on mobile devices and a web service–based Quality Detection Platform (QDP) that stores and processes data. The APP allows the building users to report criticalities through photographic acquisition and to answer a specific questionnaire. Collected data are processed by the QDP, which quantifies critical issues through the set of key performance indices (KPIs). The DSS allows monitoring buildings at the regional scale and provides a classification of the most damaged buildings, which is useful for civil protection aims and for the prioritization of interventions
Fragility analysis of prestressed concrete girder bridges affected by corrosion under traffic loads
Full text linkItalian and European transportation networks include a considerable number of existing bridges, built since the early ‘60s, characterised by simply supported prestressed-concrete (PC) girders with post-tensioned steel tendons. Corrosion of tendons, which may lead to significant loss of structural capacity, cannot be detected by simple visual inspections and requires advanced and expensive testing by bridge owner companies. Therefore, procedures aimed at risk-informed prioritisation for network-scale assessment are needed, to provide fundamental support for drawing up priority lists to be followed for an optimal allocation of resources to be employed for advanced inspections and possible retrofit. The thesis presents a study on the fragility of existing PC girder bridges considering traffic loads, accounting for corrosion-induced effects. An automated framework is proposed, aiming at the efficient probabilistic structural assessment of the investigated bridge class accounting for 1) the influence of knowledge-based uncertainty related to geometric and mechanical properties and 2) different scenarios including diverse critical corrosion levels and code-compliant traffic load models. A simplified analytical method and a refined finite element method are adopted as structure modelling strategies. To simulate corrosion effects, geometric and mechanical characteristics of prestressing steel tendons are modified by reducing the steel area and stiffness, ductility and strength properties. For analytic calculations, such modifications are integrated into a specific algorithm able to estimate variations in flexural and shear bearing capacity of critical cross-sections. In the thesis, the framework is tested with reference to a dataset of case-study superstructures with different span lengths and numbers of beams. The obtained fragility curves are deeply discussed, focusing on the corrosion effect on structural fragility and highlighting the variation of the corrosion-induced increase in fragility among the selected bridge archetypes. Although the proposed methodology presents some simplifications, it could improve the current practices of risk prioritisation, by supporting transportation authorities in ensuring the safety of the existing bridge stock
Seismic Vulnerability Assessment of an Old Stone Masonry Building Aggregate in San Pio delle Camere, Italy
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A mechanical model for the seismic vulnerability assessment of old masonry buildings
No full textThe paper discusses a mechanical model for the vulnerability assessment of old masonry building aggregates that takes into account the uncertainties inherent to the building parameters, to the seismic demand and to the model error. The structural capacity is represented as an analytical function of a selected number of geometrical and mechanical parameters. Applying a suitable procedure for the uncertainty propagation, the statistical moments of the capacity curve are obtained as a function of the statistical moments of the input parameters, showing the role of each one in the overall capacity definition. The seismic demand is represented by a response spectra; vulnerability analysis is carried out with respect to a certain number of random limit states which depend on the building parameters. Fragility curves are derived taking into account the uncertainties of each quantity involved
I materiali dell’ Arte Nova portoghese in Casa Major Pessoa ad Aveiro: caratterizzazione e confronto con edifici coevi in Bologna
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Materiales y tecnologías en la Arquitectura Modernista: casos de estudio de decoración de fachadas en Italia, Portugal y Polonia persiguiendo una restauración racional
Full text linkThe results of a diagnostic survey on the materials of representative Art Nouveau buildings in Italy, Portugal and Poland are here presented and compared, as a contribution to their understanding and, hence, to support compatible restoration. In particular, the facade decorations were investigated for the appraisal of their materials and technologies, often neglected in current maintenance/restoration works and so cancelled, leading to a severe loss in architectural image. The ongoing diagnostic campaign, in collaboration among different universities, is aimed to set up a database on materials and technologies of Art Nouveau facade decorations at a European scale, as a technical-scientific background for the highlighting of preservation guidelines
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
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