Ottimizzazione di elaborazioni termografiche per il monitoraggio dell’umidità di risalita in edifici murari risanati con tecnologia a neutralizzazione di carica

Rising damp in masonry buildings is a challenging issue and a continuous threat to the conservation of historical heritage. Moisture in the walls can provoke irreversible damage to artistic assets, due to the triggering of chemical, physical and mechanical deterioration phenomena (e.g., spalling, migration of salts). New technologies based on electric charge neutralization (CNT®) permit non-intrusive and effective actions to counteract the rising damp and stabilize the recovered conditions with time. IR thermography is widely used for diagnostics and to validate those systems, by comparing thermograms before and after the installation up to fully operational conditions. In this paper, an analytical procedure aimed at optimizing the processing and the interpretation of thermograms is proposed. It is based on the analysis of 220 thermograms captured on 33 masonry buildings in Italy, whose results were also compared with gravimetric tests, where available. Numerical indexes were computed based on statistical analyses of the relative thermal gradients. The research also pointed out the need of specific protocols for the correct application of IR thermography onsite, so that a reliable comparison among the results can be carried out to validate the effectiveness of systems aimed at protecting the buildings.