Fire damaged concrete—the potential for on-going deterioration post-fire in concrete heated to temperatures of less than 300°C

In fire damaged concrete there is the potential for the hydrated calcium alumina sulphate minerals to be decomposed due to heating leaving the sulphate compounds in the paste in a meta-stable form that can re-form as soon as there is a source of moisture and the temperature drops. Laboratory testing was carried out to confirm whether or not such expansion might occur and over what timescale that expansion might occur.