NaCl-related weathering of stone: the importance of kinetics and salt mixtures in environmental risk assessment

Abstract Salt weathering is one of the most important causes deterioration in built environment. Two crucial aspects need further investigation to understand processes and find suitable measures: impact different climatic environments properties salt mixture crystallization. We demonstrate importance kinetics quantifying crystallization dissolution cycles by combining droplet capillary laboratory experiments with climate data analysis. The results proved that times for pure NaCl are typically slower than crystallization, while thermodynamic modelling showed a lower RH eq (65.5%) (commonly found heritage) compared its as single (75.5%). Following results, minimum time 30 min considered two main thresholds could be applied predicted number dissolution/crystallization was significantly dependent on measurement frequency (or equivalent averaging period) data. An analysis corresponding rural urban demonstrated spatial phenomena (such heat island) cycles. findings fundamental improve appropriate timescale windows can illustrate methodology quantify realistic risk assessment procedure. basis future work accuracy including mixtures.