Cit:Nunes.etal:2014
| Autor | Nunes, C. and Slížková, Z. and Delgado Rodrigues, J. |
| Jahr | 2014 |
| Titel | Sodium sulphate test on lime-based mortars: attaining degraded material to test conservation products and assessing salt resistance |
| Bibtex | |
| DOI | 10.5165/hawk-hhg/261 |
| Link | Datei:28 SWBSS-2014 Nunes etal.pdf |
| Bemerkungen | In: De Clercq, Hilde (editor): Proceedings of SWBSS 2014. Third International Conference on Salt Weathering of Buildings and Stone Sculptures Royal Institute for Cultural Heritage, Brussels, Belgium, 14-16 October 2034, S. 389-404 |
Eintrag in der Bibliographie
| [Nunes.etal:2014] | Nunes, C.; Slížková, Z.; Delgado Rodrigues, J. (2014): Sodium sulphate test on lime-based mortars attaining degraded material to test conservation products and assessing salt resistance. In: Hilde De Clercq (Hrsg.): Proceedings of SWBSS 2014 3rd International Conference on Salt Weathering of Buildings and Stone Sculptures,KIK-IRPA, Royal Institute for Cultural Heritage Brussels 389-404, 10.5165/hawk-hhg/261. |   |
Keywords[Bearbeiten]
sodium sulphate, lime, metakaolin, microporosity, hydrophobicity
Abstract[Bearbeiten]
Four mortar mixtures were subjected to a sodium sulphate test, formulated to obtain degraded material for the further testing of conservation products and to estimate its salt resistance based on their hydric and hygric parameters. The ageing test involves cyclic conversion of thenardite-mirabilite. The cycle comprises of: the drying stage, salt absorption by capillarity, cooling and finally a total immersion in water. Water absorption by capillarity and microporosity determined by mercury porosimetry, were found to have a significant effect on the amount of salt absorbed consequently reflecting the induced damage. The experimental results support the theoretical view that micropores smaller than 0.1 m in radius have a critical influence on the damage induced by sodium sulphate. Lime-metakaolin mortar proved to be extremely salt-susceptible in respect to lime mortar. The addition of linseed oil to both lime and lime-metakaolin mortar improved the salt resistance of both materials by granting hydrophobicity and restraining the absorption of salt. The ageing test used was successful in attaining lime mortar specimens to exhibit degradation patterns parallel to naturally exposed material, therefore can now be used for the testing of conservation products.