Thousand-year-old nuraghi to be protected from rain and frost, the main enemies of these archaeological monuments in Sardinia. The danger is also sudden changes in temperature: the water, when freezing, expands and causes breakages in the structure of the stone. But salts also create dangerous pressures when water evaporates.
This is what emerges from a mathematical model developed by Sardinian researchers. The risks, but also a possible remedy for these damages, were illustrated in a study by Sardinian researchers published in the international journal Case Studies in Construction Materials. A "fuzzy" model was created (a procedure that uses variables not simply as numbers but with decisions that overlap without rigid classifications) to monitor and protect nuraghi or archaeological sites from degradation linked to weather.
The test was carried out at the Genna Maria site, in Villanovaforru, about sixty kilometers from Cagliari. «Thanks to the interaction between different variables (properties of the materials used and environmental conditions: temperature, relative humidity, solar radiation, wind speed and direction)», explain the authors of the discovery, «we were able to estimate the periods in which the structure is more exposed to degradation. The months of greatest vulnerability were January, February and December. We compared the model's predictions with the phenomena observed on site and with the results of accelerated aging tests in the laboratory, confirming the reliability of the model."
But the "save nuraghi" system can be applied everywhere, perhaps even on the giants of Mont'e Prama, or on other archaeological sites. The protagonists of the research are Marta Cappai (fixed-term researcher), Giorgio Pia (associate professor in Science and Materials Technology in the Department of Mechanical, Chemical and Materials Engineering of the University of Cagliari, Ulrico Sanna (retired full professor) Data management could be entrusted to artificial intelligence in the future.
(Unioneonline)