Cit:Arizzi.etal:2014
Autor | Arizzi, A. and Viles, H. and Martin-Sanchez, I. and Cultrone, G. |
Jahr | 2014 |
Titel | Testing the durability of hemp-based mortars under Mediterranean climatic conditions in coastal and inland areas: does the presence of salt alter hemp bio receptivity? |
Bibtex | |
DOI | 10.5165/hawk-hhg/244 |
Link | Datei:26 SWBSS-2014 Arizzi 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 2017, S. 357-370 |
Eintrag in der Bibliographie
[Arizzi.etal:2014] | Arizzi, A.; Viles, H.; Martin-Sanchez, I.; Cultrone, G. (2014): Testing the durability of hemp-based mortars under Mediterranean climatic conditions in coastal and inland areas does the presence of salt alter hemp bio receptivity?. 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 357-370, 10.5165/hawk-hhg/244. |
Keywords[Bearbeiten]
hemp hurd, lime, weathering, sodium chloride, microbes
Abstract[Bearbeiten]
In this study, we assessed the durability of hemp-based mortars by means of accelerated weathering tests, simulating coastal and inland areas with a Mediterranean climate. Mortars were produced with dry hemp hurds (i.e. inner part of the stem) and three binders: dry hydrated lime, lime putty and natural hydraulic lime. Simulation of temperature and relative humidity variations, rainfall and salt attack were carried out in an environmental cabinet and programmed according to the Mediterranean climatic conditions. Only one cycle (lasting 12 days) was simulated, composed of four main steps (each step corresponding to one season). After the test, mortars did not show any apparent damage apart from the loss of some fibres from the edges of samples. Mineralogical (by means of X-ray diffraction), microscopical (by means of environmental scanning electron microscopy) and microbiological studies on samples allowed a more detailed assessment of the response of the three types of mortars to weathering conditions, especially when they were combined with the attack of salt. In particular, it was found that the presence of salt delayed mortar hardening under the simulated weathering conditions and that it induced the colonization of more microbial species. However, salt was mainly washed away by the rainfall simulated in the cabinet; therefore it did not cause any efflorescence on, or damage to, the samples. Among the three mortar types, the one with natural hydraulic lime showed the least deterioration (lowest mass variation and chromatic change) and was attacked by the lowest number of microbe species. This study demonstrates that hemp-lime mortars perform well under Mediterranean climates and that their use in coastal areas is also suitable, provided that natural hydraulic lime is used and that protective measures against salt attack are adopted during the first weeks after mortar application.