Microclimatic monitoring of a semi-confined archaeological site affected by salt crystallisation

The aim of the research is to investigate the role of the microclimatic conditions and their variations on the decay due to salt crystallisation, observed in a semi-confined archaeological site, in an urban area. A microclimatic monitoring was carried out in the site to detect temperature and relative humidity and their respective variations. Statistical methodology was conducted to examine the microclimatic data with seasonal, monthly and daily analyses. Different zones of the site were monitored and a microclimatic zoning was detected. The outside environment influences the most external zones of the site, while in the confined ones a high relative humidity was detected in all the seasons. The comparison between the hygrothermal conditions monitored in the site and those thermodynamic favourable to salt crystallization revealed a very harmful risk of salt damage for the archaeological structures.