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Vadose Zone Hydrogeology in the United States
Published in L.G. Wilson, Lorne G. Everett, Stephen J. Cullen, Handbook of Vadose Zone Characterization & Monitoring, 2018
Volcanic tuff is a granular pyroclastic rock which may be very porous and almost nonindurated except in the central parts of thick beds where welded tuff is common (Winograd, 1971). Fractures in the dense welded portions provide sufficient permeability so that they constitute important aquifers where they are saturated with water. The nonwelded tuff generally has a permeability measured in the millidarcy range or less (Davis, 1969). In mountainous desert areas of the West, the vadose zone may exceed 500 m in thickness in tuff.
Underground caverns in volcanic rocks: Geological aspects and associated geotechnical behaviour of pyroclastic rocks
Published in Tatiana Rotonda, Manuela Cecconi, Francesco Silvestri, Paolo Tommasi, Volcanic Rocks and Soils, 2016
Volcanic tuff represents a series of rock from volcanic origin, generally having a petrographic composition of andesite or dacite. The high viscosity to the magma induces blast events, with ashes and other volcanic debris blown apart by explosing gases and followed by the settlement of ashes in layers.
The analysis and the diagnostic investigation of tuff masonry structures of a historic villa in Naples
Published in Claudio Modena, F. da Porto, M.R. Valluzzi, Brick and Block Masonry, 2016
L. Cantini, M.A. Parisi, C. Tardini, G. Cardani
The volcanic origin of tuff gives it a particular structure and typical mechanical characteristics. Tuff is generally a porous stone with a consolidated ash matrix and inclusions of different materials and dimensions, making it a rather inhomogene- ous material. As a result, the stone has low density, is relatively soft in terms of strength, but fairly easy to shape in blocks for construction. In the area of Naples, the so-called "yellow tuff" is the most common local variety. Even within this type, however, mechanical properties may present significant variability, depending for instance on the area of origin, and therefore from the quarry. Additional variability in the behaviour of tuff masonry derives from the quality of the mortar, usually pozzolanic, and the construction modality and details. Because tuff masonry has been used for a long time in common buildings as well as in heritage ones, the extension of the corresponding building stock and the current need to assess the buildings safety levels especially in relation to seismic risk, has given rise to an important experimental research effort by different groups of researchers and to a rich literature covering different aspects of the problem. Indications for the ranges of the main mechanical characteristics for different tuffs as well as for their composition in various masonry assemblies may be found. As an example, Ceroni et al. (2004) compare mechanical properties of different tuff types. An interesting approach in Calderoni et al. (2010) aims at defining links between tuff masonry mechanical properties, assessed from experimentation, and an ensemble of other characteristics related to construction (historical period, morphology, etc.), useful for heritage buildings where direct diagnostic tests may not be feasible or possible in a significant amount. Other authors (e.g. Augenti & Parisi 2009 and 2010) investigate the post-elastic behavior of this masonry in order to formulate accurate constitutive models for structural analysis. Mar- cari et al. (2009) propose an interesting comparison of experimental results of compression tests from different researchers, with an extended state of the art of the relevant literature. The number of variables involved, the intrinsic variability of the material properties, and probably the need of testing standardization, makes the problem of defining properties particularly complex. The complete formulation of mechanical properties for tuff masonry is still an open research field. For the importance of tuff masonry in the Italian building stock, extended research has been carried out under the auspices of the National Civil Protection Agency with the ReLUIS Program (e.g. Lagomar- sino & Magenes, 2009).
Modelling Strategies for the In-plane Behaviour of Iron-framed Masonry Structures: Parametric Analysis on Simple Panels and a Church Façade
Published in International Journal of Architectural Heritage, 2022
Luca Umberto Argiento, Thomas Celano, Francesca Ceroni, Claudia Casapulla
A very particular case of ‘baraccato’ system is represented by masonry walls encaged in frames made of iron elements, present in the Ischia Island and dated back to the end of the 19th century. This technique consists in the realization of a mixed iron-masonry structure made of tuff masonry load-bearing walls embraced with two external layers of slender iron profiles. Tuff is a volcanic stone widely diffused in the Southern Italy, especially in the Campania region, and largely used as construction material over the time due to its lightness, workability and good mechanical and insulation properties. A limited use of the iron-masonry ‘baraccato’ system was adopted in the reconstruction of the Ischia Island, particularly around Casamicciola Terme, after the catastrophic seismic event of 1883. As reported in the Municipality indications for the post-seismic reconstruction, the use of the iron ‘baraccato’ system was mandatory for buildings of public interest (Luongo, Carlino, and Cubellis 2006), such as the huge building of “Pio Monte della Misericordia” (Figure 2a) and the Church of Santa Maria Maddalena (Polverino 1998) (Figure 2b), which represent interesting case studies of such a resilient seismic system.
Analysis of rock-socketed piles loaded in axial compression in Mumbai region based on load transfer characteristics
Published in International Journal of Geotechnical Engineering, 2019
R. U. Kulkarni, D. M. Dewaikar
The geology of the Mumbai region is composed of considerable amounts of evolved rock types such as Basalts, Breccias, Rhyolites, Trachytes and Felsic and basic Tuffs. They are formed as sub-aerial eruption and are all Basaltic in composition. The different types of formation processes have led to different types of rocks. Some rocks are formed from magmatic gases that produce gas cavities. This sometimes chemically alters the basalts and the rendered Hydrothermal Alterations (HTA) are poor in quality. Tachylitic basalts are formed as very fine grained variety, since their degree of crystallisation is very low and they consist mostly of basalt glass. Tuff is formed by the process of ejection of consolidated volcanic ash ejected from vents during the volcanic eruption.
Adsorption of Azorubine E122 dye via Na-mordenite with tryptophan composite: batch adsorption, Box–Behnken design optimisation and antibacterial activity
Published in Environmental Technology, 2023
Hatun H. Alsharief, Nada M. Alatawi, Ameena M. Al-bonayan, Salhah H. Alrefaee, Fawaz A. Saad, M.G. El-Desouky, A.A. El-Bindary
Volcanic tuffs, composed of volcanic ash and various fragments, often contain natural zeolites with their unique porous structure. When volcanoes erupt, these materials are blasted from the vents into the world around them. It's an awe-inspiring phenomenon one that will surely captivate you [16]. Natural zeolites are an amazing hydrated aluminosilicate that possess some extraordinary properties that allow them to be highly sought after for countless environmental strategies. Not only do they have impressive ion exchange and sorption capabilities, but they are also economically viable materials that could boost the effectiveness of various technological processes with their remarkable physicochemical features [17].