1,720,983 research outputs found
Deepening of hydrographic pattern and slope stability: some sliding phenome¬na in the Mio-Pliocene terrains of central-southern Marche (central Italy).
No full textUn esempio di cartografia geomorfologica applicativa su base morfometrica per lo studio dei centri abitati instabili.
No full textCarta geomorfologica dell'area circostante l'abitato di Monte San Martino (Prov. di Macerata, medio bacino del Tenna).
No full textStability and environmental problems due to groundwater level raising in the abandoned Gavorrano mine.
No full textProblematiche geotecniche e idrogeologiche nel sito della ex miniera di Gavorrano (Toscana)
No full text
System Integration for Masonry Quality Assessment: A Complete Solution Applied to Sonic Velocity Test on Historic Buildings
No full textThe preservation of Built Cultural Heritage requires a careful diagnosis of the problems that characterize the historical masonries, through investigations aimed at assessing the quality of natural or artificial stone materials of which they are made. In particular, the diagnostics of masonry through Non-Destructive Techniques (NDT) is useful to deepen the knowledge of the construction characteristics, evaluate the state of conservation, and to monitor the effectiveness of the restoration interventions. Among the NDTs, the Sonic Velocity Test is largely used for evaluating the consistency of masonry and allowing the on-site identification of internal defects like fractures, voids, and detachments. The research involves the development of a complete management solution for the sonic measurements of different types of masonry and load-bearing elements. This solution consists of a website-based collaborative platform, a mobile/desktop application, and a reporting tool, which allows data processing from the on-site survey to their visualization and dissemination. The application of this system has been carried out by the LAM Laboratory of the Department of Earth Sciences (University of Florence) to evaluate the masonry quality in several historical civil and religious buildings and to improve the approach to diagnostics of Cultural Heritage
Mortar Characterization of Historical Masonry Damaged by Riverbank Failure: The Case of Lungarno Torrigiani (Florence)
Full text linkThe research of structural masonry associated with geo-hydrological hazards in Cultural Heritage is a multidisciplinary issue, requiring consideration of several aspects including the characterization of used materials. On 25 May 2016, loss of water from the subterranean pipes and of the aqueduct caused an Arno riverbank failure damaging a 100 m long portion of the historical embankment wall of Lungarno Torrigiani in Florence. The historical masonry was built from 1854–1855 by Giuseppe Poggi and represents a historical example of an engineering approach to riverbank construction, composed of a scarp massive wall on foundation piles, with a rubble masonry internal core. The failure event caused only a cusp-shaped deformation to the wall without any shattering or toppling. A complete characterization of the mortars was performed to identify the technologies, raw materials and state of conservation in order to understand why the wall has not collapsed. Indeed, the mortars utilized influenced the structural behavior of masonry, and their characterization was fundamental to improve the knowledge of mechanical properties of civil architectural heritage walls. Therefore, the aim of this research was to analyze the mortars from mineralogical–petrographic, physical and mechanical points of view, to evaluate the contribution of the materials to damage events. Moreover, the results of this study helped to identify compatible project solutions for the installation of hydraulically and statically functional structures to contain the riverbank
Monitoring and evaluation of sandstone decay adopting non-destructive techniques: On-site application on building stones
Full text linkThis paper focuses on the characterization approach to evaluate the decay state of Pietra Serena of historic buildings in Florence (Italy). Pietra Serena is a Florentine sandstone largely used in the city especially during the Renaissance; it is a symbol of cultural heritage of Florence and constitutes a large part of the city center, which was named a World Heritage Site by UNESCO in 1982. Unfortunately, many environmental factors negatively affect the stone, increasing damage and the danger of falling material. Any detachment of stone fragments, in addition to constitute a loss in cultural heritage, can be dangerous for citizens and the many tourists that visit the city. The use of non-destructive techniques (NDTs) as ultrasonic and Schmidt hammer tests can quantitatively define some mechanical properties and help to monitor the decay degree of building stone. In this study, the NDTs were combined with mineralogical, petrographical, chemical and physical analyses to investigate the stone materials, in order to correlate their features with the characteristics of the different artefacts in Pietra Serena. Correlations between the NDTs results and the compositional characteristics of the on-site stone were carried out; such discussion allows to identify zones of weakness and dangerous unstable elements
Thermal stress in the Apuan marbles: Relationship between microstructure and petrophysical characteristics
No full textApuan marbles originating from different zones of the Apuan Metamorphic Complex have been
characterized from the chemical, petrographical, microstructural and physical points of view. All
samples were subjected to accelerated ageing by thermal cycling and their petrophysical parameters
evaluated. After accelerated ageing, all samples show an increase in total open porosity and/or porosity
evaluated with Hg porosimeter in the range of pore sizes between 0.0037 and 150 mm. The greatest
variations were recorded in the coarse and fine-grained marbles with straight grain boundaries.
Two trends were observed in variation of the ratio of Hg-porosity to total open porosity after thermal
cycling: either an increase in total open porosity not followed by a proportional increase in Hg-porosity
or an increase in Hg-porosity proportional to an increase in total open porosity.
During total immersion tests, an increase of the water absorption was observed for those samples
characterised by a high ratio Hg-porosity/total open porosity with a unimodal distribution of Hgporosity.
In the case of water absorption through capillarity, the samples that suffer a higher increase
are those characterised by a bimodal pore size distribution, even if they possess low Hg-porosity. This
behaviour underlines that in the aged samples, subjected to the two different mechanisms of water
absorption, the pore size distribution plays an important role
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