Accelerate ageing on building stone materials by simulating daily, seasonal thermo-hygrometric conditions and solar radiation of Csa Mediterranean climate

Abstract

The maintenance plan of ancient and contemporary buildings today takes on strategic importance and should include the identification of climatic environment where the structures are located. Researcher are trying to evaluate the response to weathering of the building materials by accelerated ageing tests. This technique often consists of the ‘‘aggravations practice”, by subjecting materials to extreme climate parameters not representative of the real environment conditions. For this reason, this type of ageing pre- sents a lot of criticisms. This research addresses the lacking of literature about the realistic simulation of a determinate environment/climate on building stone materials. The aim of this research is to understand if it is possible to recreate in laboratory the pathologies observed on building stones of ancient monuments from Sardinia (Italy) by simulating the climatic context of location. To do so, samples were undergone to accelerated cycles of thermo-hygrometric conditions and solar radiation for simulating realistic param- eters of Csa Mediterranean climate. Monitoring of some physical/mechanical properties before and after ageing indicates an overall decohesion of samples, the appearance of decay patinas and a slight worsen- ing of mechanical resistances. A mathematical equation relates the ageing test duration (6 months) with the hypothetical outdoor exposure quantifiable in %18 years for samples evolved to temperature and humidity cycles while %3.7 years for the samples subjected to only solar radiation. However, the test should to be reproduced in the natural outdoor environment to correlate and verify the reliability of the obtained data (test the test).