1,721,031 research outputs found
Structural design criteria for safety by monitoring of the architectural heritage damage: state of the art reviews
No full textThe events that mainly undermine structural safety are both earthquakes, ground subsidence, natural
disasters (landslides, floods, hurricanes), both degradation, neglect and lack of maintenance, or even
improper maintenance.
So, earthquakes aren't the only responsible for buildings collapsing: some structural failures, occurred
in the city of Naples, are connected to the characteristics of its subsoil permeated by underground
cavities that can turn into huge ‘holes’ swallowing the foundations of buildings. In 2015, in the centre of
Naples, a historic building used as the Faculty of Veterinary Medicine of the Federico II University
collapsed. Few premonitory signs (creaks during the night) preceded the disaster. Same fate for an
important building, located on the Riviera di Chiaia, where it was said that the causes were to be found
in the excavations of the adjacent underground.
At the light of most recent events too, as the collapse of part of a church façade in piazza Cavour
(Naples, 20 January 2021), which seems to be attributable to the floor of an adjacent palace in Vico ai
Miracoli, the work aims to explore the most suitable approach possibilities particularly refers to masonry
structures classifiable as ancient buildings.
For many years now, the design has been adapting to earthquake criteria, but it has not yet adapted to
‘other’ events such as bursting a pipe or a terrorist attack or even a progressive simple leaching of the
foundation soil.
So, it is important to initiate a discussion on issues about the correct approach to safe structural design
for the historical heritage, respect to events of a different kind other than dynamic actions
The sources of antipassive constructions. A cross-linguistic survey
No full textAntipassive constructions may be polysemous, with aspectual and modal functions other than patient demotion, and may differ with respect to the way agents and patients are coded. This paper explores the hypothesis that at least some of these differences can be explained by taking into account the diachronic sources of these constructions, which hold the key to some regularities. The sample includes the 48 languages with an antipassive in WALS (Polinsky 2013) + 50 languages in which an antipassive or a functionally equivalent construction is attested. These functionally equivalent constructions are generally not labelled as antipassives in grammatical descriptions, and alternative labels such as depatientive, deobjective, unspecified object construction, etc. are used. The diachronic sources of all these constructions are identified drawing on two kinds of evidence: (i) etymological reconstructions based on the comparative method; (ii) synchronic resemblance between (some features of) the source construction and (some features of) the target construction. Four main sources are found to be recurrent in the sample: (i) agent nominalizations; (ii) generic/indefinite elements filling the object position (e.g. person for animate objects, (some)thing for inanimate objects); (iii) action nominalizations, either alone or accompanied by a light verb like ‘do’ (≅ do the washing); (iv) morphemes encoding reflexive and/or reciprocal actions. For each of these sources, a diachronic scenario is sketched through which the antipassive construction might have developed out of the source
A MODAL APPROACH TO ACTIVE CONTROL OF MASONRY ARCHES
No full text10th Int. Conf. Of Modeling and Simulation Based Engineerin
Stability analysis and seismic vulnerability of large masonry domes
No full textThis research specifically deals with the issue of the stability of the dome of St. Francesco di Paola (1816) in Naples. It represents the largest dome of its type and is the most significant example of Neapolitan Neoclassical architecture and as such generates great interest due to its solid and impressive structure. Structural analysis of the dome is performed using Heyman's Theory of Limit Analysis for masonry structures and, in particular utilises traditional methods that make use of a static approach based on graphic statics and on the interpretation of thrust lines of stone arches. As is well known, displacements are common in historic masonry structures due, for example, to consolidation of materials, imperfections in construction or differential settlements in foundations. The structural method applied in this work does not aim to define the cause of these displacements but rather seeks to understand their influence on the stability of the construction. With this perspective, in addition to the static analysis, a kinematic analysis approach has been necessary to enable an understanding of the range of possible movements of the masonry structure. Thus, the research of the dome’s minimum thrust has been checked both by static and kinematic approaches in order to assess the safety of the construction. Furthermore, the effects of earthquakes have been explored. By introducing horizontal forces proportional to the weight, it has been possible to assess dome stability under horizontal actions and to determine the limit value of the dome inclination for which the masonry is still entirely compressed. © 2019, International Masonry Society. All rights reserved
On the statics of large domes: A static and kinematic approach for San Francesco di Paola in Naples
No full textThe aim of this paper is to establish a general methodology of approach to assess the safety of the architectural heritage. Starting to a "case study", the problem of the behavior analysis of masonry buildings has been developed on the basis of some simple hypotheses about the material and on the basis of theoretical concepts. The Elastic Theory, used to check modern structures, is not suitable for masonry, material much more heterogeneous and complex. As demonstrated by the ancient builders, the most appropriate theory to study historical constructions is the Limit Analysis [1]: a better understanding of the mechanics for these structures is needed, since it is not the stress the most important parameter for masonry, but it is the stability [2]. The case approached deals with the dome of the Basilica of San Francesco di Paola in Naples, designed and built by the Swiss architect Pietro Bianchi in the nineteenth century, for the royal will of Ferdinand IV of Bourbon [3,4]. In order to assess this structure, the limit analysis approaches are here compared and, on the basis of classical limit analysis, local mechanisms are considered. A static (safe theorem) and a kinematic approach are applied to the structure by means of equilibrium limit conditions and kinematically admissible collapse mechanisms. © 2018 The International Masonry Society (IMS)
Optimization of cutting process for ancient masonry: The Greek gymnasium in Naples
No full textIn 2003, an ancient Greek Gymnasium was found in Naples, Italy, during the excavation for a new underground station. The artifacts had to be cut into blocks to be temporarily removed from the site and then reallocated after the end of the work. In this article, after describing the results of the chemical analyses and mechanical tests performed on the masonry specimens extracted from the gymnasium, a model to describe the cutting process is proposed. By means of this model, the optimal relations between kinetic, static, and energy quantities have been found, which can improve the regularity of the cutting process, permitting to minimize damage on bricks and mortar. A key physical quantity - called the "cutting strength" - is introduced and calculated through back analysis, starting from the experimental data recorded on site. The values of the cutting strength can be related to the results of the compression tests by means of a scaling law obtained through a fractal approach. Finally, a model for the wear of the cutting tools, accelerated by the dry cutting conditions, is also put forward. Copyright © Taylor & Francis Group, LLC
ABOUT THE OPTIMAL DESIGN OF ISOLATION SYSTEMS FOR ELASTIC STRUCTURES SUBJECT TO SEISMIC ACTION
No full textTHE 2ND EUROPEAN CONFERENCE ON STRUCTURAL CONTRO
TECNICHE DI APPROSSIMAZIONE MODALE-RISPOSTA DINAMICA DI UN ELEMENTO STRUTTURALE IN UN EDIFICIO DEL XVI SEC.
No full textThe neoclassical dome of san francesco di Paola in Naples. A study on form and stability. (Aimeta 2017)
No full textThe Basilica of San Francesco di Paola, located at the west side of Piazza del Plebiscito, historic center of Naples, was built as a completion of the square in front of the Royal Palace by the will of King Ferdinand IV (1816), designed by the Swiss architect Pietro Bianchi. The "The Bourbon Temple" is mainly characterized by its imposing coverage with hemispherical dome, which protrudes from the complex. It directly refers to the Pantheon for its geometric relations and proportions, its formal and compositive aspects, although it is not completely hemispherical and its interior does not enjoy the spatiality of its model. Furthermore in origin the dome ended with a central oculus in which, even today, the structural forces converge and balance. Subsequently, a lantern was placed on the oculus, which is a conical element completely in glass that allows the passage of light. The aim of this work is the study of the stability of the dome that, firstly, allows to specify the overall safety of the structure in its current state, especially with regard to statics. Secondly, to assess the degree of seismic safety of the structure, identifying the potential conditions of vulnerability in case of earthquake. The static analysis has been performed, by using the graphical method, according with the principles of the limit analysis applied by Heyman to the masonry structures. The methodological innovation consists in the use of the traditional methods of graphical calculation of masonry structures, interconnected with the new antiseismic norms in the territory. The operational aspect of the work is contained in the interdisciplinarity of scientific fields, with the aim of obtaining a complete knowledge of the monument in its current condition without using an elastic analysis, which would not be suitable for the study of historical building
A limit analysis approach for masonry domes: the basilica of San Francesco di Paola in Naples
No full textThe object of the present study is the basilica of San Francesco di Paola, an historical structure that well lends itself to use the graphic method of statics to analyse its stability for a two-fold reason: on the one hand, it is an interesting structure being dominated by a dome of considerable size with a solid appearance, and on the other, it is an entirely masonry structure for which no consolidation interventions with different materials have been necessary so far. This paper applies limit analysis based on the geometric equilibrium of the dome starting from detailed surveys of the church, from the knowledge of its history construction to the comprehension of the entire building. The study carried out enriches previous researches developed around the same case study, and the new contribution is integrated by the analysis of stability of the buttress system that completes the work on the vertical loads, providing a more detailed assessment of the safety level of the structure
- …
