Alteration of stone materials on Sardinian medieval monuments: physical, chemical and petrographic analysis for their restoration and preservation (Abstract/Comunicazione in atti di convegno)

Type

• Prodotto della ricerca (Classe)
• Abstract/Comunicazione in atti di convegno (Classe)

Label

• Alteration of stone materials on Sardinian medieval monuments: physical, chemical and petrographic analysis for their restoration and preservation (Abstract/Comunicazione in atti di convegno) (literal)

Anno

• 2014-01-01T00:00:00+01:00 (literal)

Alternative label

• S. Columbu*, M. Marchi*, M. Palomba**, F. Sitzia* (2014)
  Alteration of stone materials on Sardinian medieval monuments: physical, chemical and petrographic analysis for their restoration and preservation
  in Conference on Cultural Heritage and New Technologies, CHNT 19, Session: Urban archeology and Processing - Rubble, Ruins and Reading, Specific Approaches in Analysis, Trying to Let the Remains Telling the Story, Vienna, November, 3-5, 2014
  (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori

• S. Columbu*, M. Marchi*, M. Palomba**, F. Sitzia* (literal)

Pagina inizio

• 21 (literal)

Pagina fine

• 22 (literal)

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• http://www.chnt.at/wp-content/uploads/WS19_Abstractband.pdf (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#titoloVolume

• Conference on Cultural Heritage and New Technologies, CHNT 19, Session: Urban archeology and Processing - Rubble, Ruins and Reading, Specific Approaches in Analysis, Trying to Let the Remains Telling the Story (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#pagineTotali

• 2 (literal)

Note

• Abstract (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni

• *Dipartimento di Scienze Chimiche e Geologiche - Università di Cagliari ** ISAC - Istituto di Scienze dell'Atmosfera e del Clima (literal)

Titolo

• Alteration of stone materials on Sardinian medieval monuments: physical, chemical and petrographic analysis for their restoration and preservation (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autoriVolume

• Stadtarchäologie Wien (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#curatoriVolume

• Wolfgang BÖRNER (literal)

Abstract

• Sardinian medieval monuments are mainly made up by volcanic rocks (pyroclastites/ignimbrites), minor granitoids and sedimentary rocks, that show a more or less significant chemical-physical alteration. Mineral-petrographic features, physical properties related to petrogenetic processes, as well as manufacturing, strongly influence type and intensity of stone-decay. The granitoids show an alteration degree less than the other rock-types, due to low porosity (<10%) that does not favour an easy absorption of circulating solutions, thus avoiding the water-rock interaction and hydrolysis. In a few cases, a physical intra-crystalline decohesion, that involves a rounding of the sharp edges of ashlars, can occur, while, in chemical/mineralogical terms, oxidation patinas and the chloritization of mica minerals can be observed. The pyroclastites/ignimbritites, widely used in medieval architecture for the excellent workability, are 22 affected by greater alteration due to the different mineral/chemical composition, mainly including glass (>70%), and physical features (higher porosity, 20-45%) due to a variable welding degree. Chemical alteration is not always evident since is more slow than the physical degradation (with macroscopic forms of pitting, exfoliation, alveolation). The limestones with low porosity (<10%) show an alteration that generally occurs on the outer surface of ashlars (with solubilization-reprecipitation processes), while sandstones and calcarenites (porosity >25%) generally show an advanced stages of decay, with physical macroscopic forms similar to those of the pyroclastites. The chemical alteration is also present, in particular on carbonate cement. To make a contribution to the preservation of sardinian monuments, this paper suggests a new approach to define the different alteration-modes of rocks in function of their local exposure to the weather, studying: 1) the changes of physical properties on surface of stone (porosity, water absorption, micro-morphology) determined through laboratory tests and photogrammetry observations, 2) the alteration phases present on surface (e.g., secondary minerals, soluble salts) determined by mineralogical (XRD) and chemical (XRF) investigations. (literal)

Prodotto di

• Institute of atmospheric sciences and climate (ISAC) (Istituto)
• Diagnostica degli effetti climatici e microclimatici sul patrimonio culturale (PC.P03.004.001) (Modulo)

Autore CNR

• MARCELLA PALOMBA (Unità di personale interno)

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• Parole chiave di "Alteration of stone materials on Sardinian medieval monuments: physical, chemical and petrographic analysis for their restoration and preservation" (Insieme di parole chiave)

Incoming links:

Prodotto

• Institute of atmospheric sciences and climate (ISAC) (Istituto)
• Diagnostica degli effetti climatici e microclimatici sul patrimonio culturale (PC.P03.004.001) (Modulo)

Autore CNR di

• MARCELLA PALOMBA (Unità di personale interno)

Insieme di parole chiave di

• Parole chiave di "Alteration of stone materials on Sardinian medieval monuments: physical, chemical and petrographic analysis for their restoration and preservation" (Insieme di parole chiave)