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The rock structure is characterized by the presences of elongated mafic enclaves, up to 20 cm with aspect ratio up to 1 : 20, some banded (mafic and felsic bands). Small rounded mafic enclaves are also present (2–3 cm). Felsic enclaves up to 40 cm 109ocurr either as fine to very fine-grained or as very coarsed-grained. All these structural elements disrupt the rocks décor. The rock is classified according to its mineral composition (Table 1) as a granite (Strohmeyer, 2003; Grimm, 2018).
Table 2: Physical properties of Kösseine Granite.
| Physical properties (units) | Grimm (2018) | Strohmeyer (2003) | ||
| Bulk density (g/cm3) | 2.67 | 2.67 | ||
| Matrix density (g/cm3) | 2.69 | 2.68 | ||
| Porosity (% vol) | 0.71 | 0.11 | ||
| Average pore radii (µm) | 0.02 | |||
| Volume of capillary pores (% vol) | 0.02 | |||
| Water absorption (wt%) | ||||
| Water absorption (atm) (wt%) | 0.21 | |||
| Water absorption (vac) (wt%) | 0.27 | |||
| Saturation coefficient S | 0.79 | |||
| Water absorption coefficient [kg/m2*√t] | 0.003 | |||
| Permeability (mD) | 0.002 | |||
| Specific surface (m2/g) | 0.22 | |||
| Thermal expansion coefficient (10–6K–1) | 9.22 | |||
Table 3: Mechanical properties of Kösseine Granite.
| Mechanical properties (units) | Strohmeyer (2003) | ||||
| x-direction | y-direction | z-direction | Average | ||
| UCS (MPa) | 194 ± 11 | 194 ± 10 | 199 ± 8 | 195 ± 17 | |
| Indirect Tensile Strength (MPa) | 12.2 ± 1.2 | 10.9 ± 1.3 | 12.5 ± 1.5 | 11.9 ± 2.3 | |
| Flexural Strength (MPa) | 18.0 ± 1.1 | 19.7 ± 1.1 | 22.6 ± 0.8 | 20.1 ± 1.7 | |
| Abrasion Strength (cm3/50 cm2) | 5.8 ± 0.2 | 5.7 ± 0.1 | 5.6 ± 0.1 | 5.7 ± 0.2 | |
Physical and mechanical properties
No physical or mechanical tests were performed, nevertheless, results of Strohmeyer (2003) and Grimm (2018) were considered (Tables 2 and 3).
Kösseine Granite shows a very good behavior against atmospheric agents, directly related to its physical properties: very low porosity, low water absorption, low water uptake coefficient and permeability. These properties show that the rock is practically impermeable, and consequently extremely stable to weathering conditions.
Mechanical properties for Kösseine Granite are typical of granitic rocks, even slightly higher. Comparing its UCS (uniaxial compressive strength) values to those of the statistical study of Mosch (2008), it can be observed that they are above the median. Flexural strength is also above the median of Mosch (2008), but the indirect tension is slightly below this parameter.
Abrasion resistance values are slightly higher than those reported by Morales Demarco (2012) for Uruguayan granitic rocks, but in the range of values given by Siegesmund & Snethlage (2011).
Figure 2: Ground floor plan (modified from FADU, 2019).
Figure 3: a. Perforation with metallic insert, oxide staining and star crack; b. Missing gap presumably a product of bursting or removal of metallic insert.
110Deterioration assessment
For this activity, the building was divided in four main areas, the façades of Andes Street, 18 de Julio Avenue, Plaza Independencia and the Gallery (Figure 2). A total of 675 pieces were analysed. The basis used for this diagnosis is the classification proposed by ICOMOS (2011).
Table 4: Deterioration features present in Pilasters and Columns of Palacio Salvo (in brackets number of pieces with feature repaired).
| Deterioration | Andes | 18 de Julio | Gallery | Plaza Independencia |
| Crack | 10 | 6 | 8 | 14 |
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