Thaumasite formation in metakaolin and limestone cement formulations in cold climates: A thermodynamic investigation

Description

Marine exposure conditions present a challenge to the long-term integrity of concrete structures. With the increasing attention on using calcined clay and limestone as supplementary cementitious materials (SCMs) to reduce the CO2 footprint of cement, uncertainties regarding thaumasite formation have risen. In cold climates, these uncertainties are related to seawater exposure. This study investigates the thaumasite formation in metakaolin and limestone cement formulations when exposed to seawater in cold climates. The thaumasite formation is investigated by thermodynamic modeling, using simplified chemical
compositions of calcined clay, limestone, and seawater. The investigation is carried out based on different cement compositions, exploring the influence of limestone content on the thaumasite formation. The results based on the modeling indicate that thaumasite formation occurs at the expense of ettringite when C-S-H is consumed in all cases investigated. The volume of thaumasite is however dependent on the limestone content.

Period	25 Sept 2024 → 27 Sept 2024
Event title	10th International Conference on Concrete under Severe Conditions: Environment and Loading
Event type	Conference
Location	Madras, IndiaShow on map