Search results for " Stone"
showing 10 items of 160 documents
Integrating thermal and mechanical characteristics of historic masonry categories: Development of a Sicilian database
2021
Detailed construction analysis is essential to the compatible energy improvement of historic buildings. In-situ measurements are crucial for energy diagnosis but their use is limited, especially in vernacular architecture. This paper exposes the development of a hygrothermal and mechanical database for Sicilian historic walls. The proposed method, applied to eleven historic centres, is based on the investigation of those masonry construction features, which recur in local contexts. Preliminary results concern the case study of Petralia Sottana, where a first set of laboratory measurements of stone compressive strength and thermal conductivity was conducted, together with in-situ tests of ma…
New Architectural Models and Building Tradition: A Dialogue in Early Modern Sardinia - The Jesuit Church in Sassari
2014
L'architettura nella Sardegna di età moderna è caratterizzata da una forte continuità con pratiche antecedenti. Nella seconda metà del XVI secolo, nuovi modelli, legati in particolare alle nuove tendenze nel campo dell'architettura militare e il classicismo della controriforma cattolica, affiancano la tradizione costruttiva gotica.La chiesa dei Gesuiti di Sassari offre un interessante esempio di intreccio tra queste modalità architettoniche, causato da un improvviso cambio alla guida del cantiere. Giovan Maria Bernardoni, un architetto gesuita italiano, redasse il progetto iniziale della chiesa sul modello del Gesù di Roma, ed essa fu parzialmente costruita sotto la sua direzione. Dopo la s…
Do stones modify the spatial distribution of fire induced soil water repellency? Preliminary data
2013
Water repellency is a property of many fire-affected soils that contributes to delayed wetting rates and shows many hydrological and geomorphological consequences. Fire-induced soil water repellency (SWR) may be modulated by pre-fire soil and vegetation properties. Many studies have been carried out to investigate the relationship between SWR and these properties. But, to our knowledge, no studies have considered the effect of surface stones in the spatial distribution of fire-induced SWR. In this research, we study the occurrence and spatial and vertical distribution of SWR and its consequences on soil structure after experimental burning in a previously wettable soil under different stone…
Experimental Evaluation of a New Electromagnetic Shock Wave Source
1987
Clinical application of new shock wave sources always warrants prior experimental evaluation of the stone disintegration capabilities and characterization of the shock wave impulses. The least possible tissue traumatization is necessary for successful clinical introduction. After the spark-gap generation of shock waves with semi-ellipsoid focussing had been introduced to the urological armamentarium for extracorporeal destruction of renal and ureteral stones in 1980 (Chaussy 1982), new modes of shock wave generation have been developed. In cooperation with the Siemens Company of Erlangen, Germany, a new electromagnetic shock wave source was evaluated by in vitro and in vivo animal experimen…
The Potential Geosite of the “Libeccio Antico” Quarries: a Sedimentological and Stratigraphic Characterisation of Ornamental Stone from Mt Cocuccio, …
2018
The Custonaci marble district of western Sicily is known for the production of a valuable ornamental stone that has been, and nowadays is exploited due to its suitable properties and aesthetic qualities. The “Libeccio Antico” was, among the “marbles”, the most appreciated ornamental stone during the Baroque Age (the XVII–XVIII centuries), due to its strong polychrome contrasts from ivory to yellow, green or dark red. This polychrome pattern is the result of dissolution processes that involved an Upper Triassic peritidal limestone. The varicoloured sediments in paleocavities, collapse breccias, paleosols and neptunian dykes that occur in the “Libeccio Antico” represent the peculiar character…
Effect of steel collars on the seismic behaviour of granite and heavy stone columns
2013
Granite and heavy stone circular columns could be often find in the cultural heritage among ancient churches and historical buildings in all the Mediterranean area. Their good strength properties allowed to carry great load values, while their bright colours and aesthetical characteristics have been used by a lot of ancient architects to achieve structural solutions with great visual impact. Even if such materials have great compressive strength values, the environmental effects, such as long term effects and thermal loads, could damage the structural members, by cracking them. In this way the slenderness of the column increases, and the presence of an imposed ground motion could be very da…
Environmental impact assessment on the Monza cathedral (Italy): A multi-analytical approach
2020
This research deals with the characterization of black crusts collected from the Dome of Monza (Milan, Italy). Air pollution is responsible for the degradation of historical buildings surfaces. In urban and industrial areas, the degradation process is accelerated, due to carbonaceous particles and heavy metals emitted by combustion processes which contribute to the formation of black crust (BCs). In this study the characterization of BC was performed using different analytical techniques such as: HRSEM-EDX, IC, LA-ICP/MS and digital image analysis. In particular, the research focused on the study of "heavy metals" which contribute to the identify the main sources of pollution responsible fo…
The role of transportation and its involved sources of energy in the environmental assessment of marble producing sites
2018
Marble is acquiring large popularity as building material. Since building materials are now required to be characterized by high energy and environmental performances, marble is entailed to fulfill top-level requirements. About its environmental performances an important European Decision establishes criteria for the award of the Community eco-label to this material. Unfortunately, this Decision is focused on mining and processing activities, seemingly neglecting marble transport. In contrast, this phase affects the whole working chain because it releases (pollutant) emissions and involves the use of primary and, in case, secondary energy sources. Here, the focus is on the role played by tr…
Il miglioramento energetico nel recupero degli edifici storici. Applicazione al patrimonio architettonico palermitano
L'architettura storica può assumere un ruolo rilevante nel raggiungimento degli obiettivi europei di efficienza energetica per il settore edile, obiettivi che, tuttavia, devono essere compatibili con la conservazione del patrimonio storico e del suo valore culturale. A tal fine è necessario far riferimento ai caratteri specifici dell'architettura storica e alla sua dimensione locale. La presente tesi, sulla base di tale assunto, esamina le prestazioni energetiche degli edifici storici e il loro potenziale miglioramento, concentrandosi sul patrimonio architettonico di Palermo, caso di studio significativo per l'area mediterranea. La ricerca, condotta con riferimento sia alla scala urbana sia…
Effects of pyrolysis conditions on the porous structure development of date pits activated carbon
2012
International audience; Activated carbons were prepared from biomass of Algerian date pits for developing efficient and cheap adsorbents in the aim to remove heavy metals from waste water. Carbon adsorbents were obtained following two successive treatments: pyrolysis under dry nitrogen flow and physical activation under wet nitrogen flow. Pyrolysis process was optimized by varying some operating parameters such as temperature, nitrogen flow, heating rate and pyrolysis hold time in order to determine their effects on the porous structure development of date pits activated carbon. Chars obtained from pyrolysis process were activated with the same operating conditions (activation temperature o…