Search

The staircases represent one of the most impressive architectural expressions of the building. Many authors presented a great deal of research over the years on this matter intending to understand how they are designed and laid out. This paper is concerned with a particular structural type of masonry staircase, known as stair with open well or roman staircase. It aims to demonstrate that in masonry-vaulted staircases, the close relationship between the shape and static behavior is particularly evident, and geometry and construction are essential for their stability. The authors have proved this statement by studying Palazzo Di Majo’s open-well staircase in Naples, whose main structure consists of tuff vaults. The first part of the article is substantially descriptive and presents an in-depth description of the geometric and architectural features of the stair. The second part explains all the aspects concerning the equilibrium of this kind of stairways, within Heyman’s theory of masonry. &nbsp, Las escaleras representan una de las más imponentes expresiones arquitectónicas del edificio. Varios autores han presentado muchas publicaciones a lo largo de los años sobre este tema para entender cómo han sido diseñadas y cómo se sostienen. Este trabajo se trata sobre un tipo específico de escalera de albañilería, conocida como escalera “de ojo abierto” o “a la romana”. El objetivo es demostrar que en las escaleras con bóvedas de fábrica existe una estrecha relación entre la forma y su comportamiento estático. La geometría y la construcción son imprescindibles para su estabilidad. Los autores han demostrado esta tesis estudiando la escalera de ojo abierto del Palacio Di Majo en Nápoles, cuya estructura principal está constituida por bóvedas de toba. La primera parte del artículo presenta una descripción detallada de las características geométricas y arquitectónicas de la escalera. La segunda parte, explica el equilibrio de estas escaleras a partir de la teoría del equilibrio de estructuras de fábrica de Heyman.

La città obliqua è un progetto pilota che nacque negli anni ‘80 dal genio di un architetto napoletano, urbanista, grande appassionato di musica e della città, che offrì alla comunità un programma di sviluppo strutturato e organico, supportato da indagini approfondite e dal censimento di brani urbani dimenticati; assunse, anche, valore iconico e di riconoscibilità di una tendenza culturale maturatasi in quegli anni nell’ambito della Facoltà di Architettura, tant’è che il progetto fu messo in note da un suo allievo, famoso cantautore, che ne fece un brano musicale. L’idea progettuale anticipò, in una dimensione futuribile, ciò che molti anni dopo - e ancora oggi - forma materia di dibattito sia in ambito scientifico che sociale. Il progetto prevede il recupero di percorsi arcaici affiancati a mezzi di risalita, oggi definibili sostenibili, all’epoca connotati da elevata tecnologia ad emissioni ed impatto ridotto; una rete di collegamenti con le vie del mare e della collina, stazioni di smistamento, parcheggi sotterranei, interconnessioni con le metropolitane esistenti e con quelle all’epoca ancora da realizzare, per sviluppare una forma di mobilità pedonale realmente efficace. Questo contributo intende, per un verso, riportare alla memoria e conoscenza della comunità scientifica un episodio progettuale che, a pieno titolo, trova posto nell’ampia letteratura riguardante le grandi sperimentazioni per Napoli; per un altro, collocandosi in quell’ambito di interesse che integra dicotomicamente la rappresentazione del territorio, l’urbanistica e la trasportistica, intende mettere in evidenza la contemporaneità ed efficacia dello studio condotto nel 1984 per risolvere la mobilità a Napoli, integrandosi oggi perfettamente con il nuovo sistema infrastrutturale di cui si è dotata la città., Eikonocity. Storia e Iconografia delle Città e dei Siti Europei, V. 6 N. 1 (2021)

The aim of this research is the structural study of the hemispherical dome of San Francesco di Paola in Naples and, in particular, the evaluation of its degree of seismic safety not considering the role of the supporting structures. The methods we adopt are based on the determination of a class of purely compressive stress regimes, which are balanced with the load. Within the unilateral model for masonry (Heyman’s model), the mere existence of such a class is a proof that the structure is safe; members of this class can be used to assess the geometric degree of safety of the structure and to estimate bounds on the thrust forces exerted by the structure on its boundary. The analysis has been performed, by using both the graphical method and the membrane approach. The methodological innovation consists in the use of both the analytical and the traditional methods of graphical calculation of masonry structures, considering both vertical and horizontal loads. As a result of our analysis, we conclude that the sole dome can sustain a horizontal load of 0,577 g.

The work aims to describe the issue of the approach related to structural problems, both for valuable and minor manufacts existing in the Italian historical town centers. The heterogeneity shown by these constructive typologies should coincide with some heterogeneity of the structural approach, but this is not always feasible, so computational processes and a strict application of the norms are often used in automatically. A representative case, as an example of the above-mentioned kinds of buildings (which are valuable, but not so much as to require a tailored intervention that takes into account the whole constructive history and the changes over the time), is shown. Ricciardelli palace (or Palazzo Ricciardelli) presents a great difficulty as to the structural intervention, but the approach used was a "classical engineer approach", formulated on the basis of the new computing tools and the new constructive norms. The restoration and the consolidation of this artifact have been well conducted by technicians, but the result is an invasive intervention that doesn't respect the original structural configuration of the construction. So the paper explains and discusses some investigation methodologies, alternative to an elastic analysis, which could be used in these cases, with the awareness that they are not completely exhaustive and far far away from the determination of a general formulation for a “unique model”, which can be representative of the masonry material, as well as from a definition that catalogues all its several features.

This paper focuses on natural hazards, such as landslides and floods, and on consequent disasters that can suddenly hit extensive urban areas. The research aims to describe and detect the damages due to unprecedented rainfalls that occurred among 15th and 19th October 2015 and that have led to multiple calamitous events in the Municipalities of Benevento, in Southern Italy. It highlights the most affected locations and common phenomena in order to document the past and present situation of risk. This hydrologic event has resulted in simultaneous disasters in the different areas of the Samnium, namely overflowing of the Calore river, massive flooding, intense erosions, extensive landslides in the mountain areas and heavy damage to the constructions and infrastructures. Particularly, the research concerns the vulnerability of the existent crossing structures in the examined areas, e.g. some masonry bridges, that because of this event of flood have collapsed for a part. This brief overview wants to be a reflection on the issue of natural disasters related to the definition of risk scenarios and emergency management but especially to the extent of protecting the built heritage. The evaluation of territorial threats could be a fundamental source of knowledge to deal with future emergencies, by extending this approach all over the world, for planning and integrated development in specific geographic areas with similar constructive features and problematics.

La Basílica de San Francisco de Paula, situada en la Plaza del Plebicito, centro histórico de Nápoles, fue construida como una finalización de la plaza frente al Palacio Real por voluntad del Rey Ferdinando IV (1816), diseñada por el arquitecto suizo Pietro Bianchi. El "templo de los Borbones" se caracteriza principalmente por su imponente cubierta a cúpula semiesférica, que sobresale del complejo. Hace referencia directamente al Panteón por sus relaciones geométricas, de proporción, sus aspectos formales y compositivos, a pesar de que no es completamente semiesférica y su interior no goza de la espacialidad de su modelo. Además en origen la cúpula terminaba con un óculo central en el cual, aún hoy, convergen y se equilibran las fuerzas estructurales. Posteriormente, sobre el óculo se colocó una linterna, que es de hecho un realzado cónico completamente en vidrio que permite el paso de la luz. El objetivo de este trabajo es el estudio de la estabilidad de la cúpula que permite precisar, en primer lugar, la seguridad global de la estructura en su estado actual, en especial en lo que respecta a la estática. En segundo lugar, evaluar el grado de seguridad sísmica de la estructura, identificando las potenciales condiciones de vulnerabilidad en caso de sismo. El análisis estructural es de tipo estático, realizado a través del método gráfico, in linea con los principios del análisis límite expuestos por Heyman para las estructuras de fábrica. La innovación metodológica consiste en el uso de los métodos tradicionales de cálculo gráfico de las estructuras de fábrica, interconectados con las nuevas normas antisísmicas del territorio. El aspecto operativo del trabajo se configura en la interdisciplinariedad de campos, con el objectivo de obtener la comprensión completa del objecto en su condición actual sin utilizar un análisis elástico, que no sería adapto para el estudio de los edificios históricos.

The 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. Further-more in origin the dome ended with a central oculus in which, even today, the structural forc-es 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 anti-seismic norms in the territory. The operational aspect of the work is contained in the interdis-ciplinarity 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 suit-able for the study of historical buildings.

The paper starts by announcing its goal of comparing the information about the structural analysis of two Napolitan churches. Starting from the structural behaviour of two architectural elements, the ogival arch of the arcade of the Incoronata and the cross vault of S.Eligio, the research aims to provide a wider reflection on the method for assessing the sta-bility of historical architectures in masonry, respectively applied to a two-dimensional and three-dimensional scheme. Therefore, the study of these two Churches is presented with a dis-cussion on the results obtained with regard to the methodology approach to the analysis re-lated to their structural features. The Incoronata Church and S. Eligio are two examples of Angevin architecture in Naples and over the years both them have undergone several transformations that have changed their original appearance. By considering the Viollet Le Duc assumption that “in architecture ge-ometric proportions are established primarily on stability laws, the laws of stability derived from geometry”, the work deals with a study of the form and stability of the system of arches and of the cross vaults to investigate the geometric-configurative nature of the structural ele-ments that constitute gothic architecture.

Il presente lavoro si incentra sullo studio di alcune tipologie edilizie appartenenti alla tradizione costruttiva rurale delle aree Vesuviane, le Masserie, con particolare attenzione agli aspetti strutturali connessi alla prevenzione del rischio sismico e vulcanico. Dall’osservazione di molte architetture del passato, si evince chiaramente una strategia di protezione antisismica, realizzata in maniera intuitiva, attraverso espedienti semplici quali la geometria della pianta, le proporzioni delle sezioni e la distribuzione delle aperture, l’uso di materiali e elementi strutturali peculiari, che è stata in grado di conservare nel tempo questi manufatti. Il fine della presente ricerca, dunque, è quello di dimostrare la recuperabilità del sito a dispetto della paura del vulcano in maniera tale da individuare dei metodi da applicare per un corretto restauro antisismico, fondamentale per mitigare il rischio

The island of Nisida is located in an enchanting natural landscape of rare beauty in Phlegrean coast. Nisida has an ancient history: geo-morphological (eruptive cycle of the Campi Flegrei); mythical (the adventures of Ulysses); archaeological (summer Brutus’residence); defensive (until World War II). The defensive role of Nisida is demonstrated by its presence in the most important maps of the time. In the Angevin period, on top of the island a cylindrical watchtower was built. On its facility, in the sixteenth century, works began with the aim of the construction of ramparts tower, as noble residence of the Piccolomini and maritime surveillance (Monterey Project, 1635). In Bourbons age, two forts in Porto Paone were built, used until the Second World War. Today, the access to the island of Nisida is prohibited because inside there is a juvenile penitentiary. The current surveys of defensive architecture, recently discovered, are occasion of documentation for the enhancement of the existent.

Non-linear dynamics is generally recognized as the most reliable method to carry out analyses of structures subjected to earthquake actions. In general non-linear dynamics requires a great level of expertise, as well as cost and time necessary for calculation. The lack of suitable computational techniques has induced seismic analyses involving two classes of simplified procedures: modal approximations and constitutive and structural models with sufficient accuracy and low numerical complexities. The dynamic response of building structures subjected to seismic loads has been often examined using the single-degree-of-freedom model, that provides a good estimation of the fundamental response mode, which is normally responsible for overall structural failure. A SDOF analysis can give a preliminary assessment for a protective structure, even in cases in which the constitutive models are somewhat more complex. The rigid-plastic cantilever beam can be in fact a simple structural scheme to clarify the behaviour of more complex structures and to verify the accuracy of the numerical methods in a non-linear dynamic analysis. In general, significant differences exist between a complete building and uniform beams, nevertheless the continuum model provide useful results. This paper presents a general treatment to develop approximate solutions for rigid-plastic response of structures subjected to base harmonic pulse, that has been shown in literature as an appropriate approach to the seismic analysis. A numerical procedure has been on purpose developed, taking into account two different approaches: a step-by-step solution of the general non linear dynamic problem and the evaluation due to a modal approximate response, satisfying both kinematical admissibility requirements and boundary conditions. An estimation of the error due to the second approach is given. In order to assess the reliability of the approximate procedure it is shown that the approximation does not depend on the forcing accelerogram.

In this paper the unilateral model for masonry is applied to explain the equilibrium of vaults. In particular, the present study is concerned with the application of the safe theorem of limit analysis to spiral vaults, that is, curved constructions modeled as continuous unilateral bodies. On allowing for singular stresses in the form of line or surface Dirac deltas, statically admissible stress fields concentrated on surfaces (and on their folds) lying inside the masonry, are considered. The unilateral restrictions require that the membrane surface lies in between the extrados and intrados surfaces of the vault and that the stress function, representing the stress, be concave. Such a constraint is, in general, not satisfied on a given shape for given loads: in such a case, the shape has to be modified to fit the constraint. A particular application, namely the double spiral stair of Sanfelice’ palace in Naples, is considered.

This paper focuses mainly on high structures such as towers, skyscrapers, steeples, etc. and analyzes their structural behavior. Through examples of his- tory, as the Bell Tower of San Marco in Venice (1902), the Civic Tower of Pavia (1989) and the Twin Towers in NY (2001), that have undergone ruinous collaps- es, this text attempts to define the good rules to design tower structures with a perspective to prevention from accidental damages such as falls, earthquakes, terrorist attacks, which can invest buildings bringing them to the ground. There- fore, the work highlights new structural concepts that take into account prob- lems related to high dimensions, the robustness as crucial parameter to the security from collapse and the structural hierarchy.

The island of Nisida houses the Institute Criminal juvenile, located in a building of the thirties of the last century. Below this building are preserved ancient local Bourbon, recently the subject of excavation conducted by the current prison administration. The Memorandum of Understanding for cultural activities and research signed in March 2014 between the Department of Architecture and Industrial Design "Luigi Vanvitelli" of the Second University of Naples and the Department of Juvenile Justice of the Ministry of Justice (Italy) has the aim to promote studies to analyze the material sources and to propose the scientific survey of some buildings recently brought to light. The disciplines of the survey and the representation of the built and natural environment have provided an opportunity for knowledge and documentation of reality. This documentation assumes importance as a valuable starting point for any proposed enhancement and it allows architecture to reveal otherwise unknown to most. The survey campaign of the building housing the juvenile Criminal Institute was launched in March 2014 with the correlation of scientific scholars of the history of the island. To date they have been brought to light some rooms below and a staircase leading to the courtyard. This will allow structural and architectural survey will allow to understand whether the current foundations rest on a convent or a Roman villa.

The current code approaches for engineered systems are generally conceived on the basis of component designed philosophy, where explicit requirements are mostly specified at component level or at individual members. There is very little guidance on the overall safety and the approach for design to prevent progressive collapse as a result of abnormal loading is not standard. Several reference papers on the subject treat the problem qualitatively. Following a recent scheme in the literature, in which structural integrity is captured in the structural stiffness matrix, in this presentation we will treat the problem through a quantitative approach extending the analysis from the linear elastic case to the plastic deformation range in terms of frames removal or plastic hinges insertion. With this aim we discuss system integrity measures, and we suggest that the inverse of the stiffness matrix condition number (the so called metric distance) gives a better representation of structural integrity. We also discuss the compartmentalization problem and introduce for the first time quantitative measures of it. We finally apply such new measures to simple examples and show an optimization problem related to the structural integrity.