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Robert J. Flatt, George W. Scherer, Jeffrey W. Bullard
Abstract
Cement hydration continues to have an intriguing character, surrounded as it is by a number of intensively debated questions. Among the unresolved issues is the reason why hydration stops at a relative humidity of about 80%, even though the system still contains a fair amount of water. This short communication shows that a critical relative humidity, below which hydration should stop, can be defined from a relatively simple thermodynamic treatment.
Flatt, R.
, Scherer, G.
and Bullard, J.
(2011),
Why Alite Stops Hydrating Below 80% Relative Humidity, Cement and Concrete Research
(Accessed October 14, 2025)