Thermodynamic data for hydrated solids in Portland cement system (CaO-Al2O3-SiO2-CaSO4-CaCO3-Fe2O3-MgO-H2O)
New version CEMDATA 14.01 available
The first version of the cement specific cement database CEMDATA was published in 2007-2009 and based on work carried out at Empa (Lothenbach et al., 2008; Möschner et al. 2008, 2009; Schmidt et al. 2008) and a PhD carried out both at the University of Aberdeen and at Empa (Matschei et al, 2008). CEMDATA contains thermodynamic data (solubility product, Gibbs free energy, enthalpy, entropy, heat capacity and molecular volume) for a number of cement phases. Solubility data have been generally calculated based on a critical review of the available experimental data and on additional experiments to derive missing data or to verify the existing data. In addition, some data were estimated based on structural analogues. Where necessary, additional solubility data were measured in a range of temperatures between 0 and 100 °C. The resulting data base covers hydrates commonly encountered in Portland cement systems in the temperature range 0-100 °C, including C-S-H, hydrogarnet, hydrotalcite, AFm and AFt phases and their solid solutions.
CEMDATA contains thermodynamic data for solids found in Portland cement systems, evaluated as described in various publications (see below). Its applicability to Portland cement systems has been investigated in a number of studies.
In order to model other systems, e.g. blended or alternative cements, cement degradation, or sorption of metals in cement matrix, the CEMDATA must be critically evaluated and extended with additional pure solids and/or solid solutions.
CEMDATA at 25 °C
At 25 °C the solubility products (KS0) of the CEMDATA data set is fully consistent with the thermodynamic data for aqueous species, gases, and common minerals such as portlandite or gypsum, provided in the Nagra/PSI-Thermodynamic Data Base (Hummel et al., 2002) and can be used together with the Nagra/PSI TDB in any thermodynamic modelling software.
CEMDATA at 0-100 °C
The CEMDATA07 data base covers hydrates commonly encountered in Portland cement systems in the temperature range 0-100 °C. In the temperature range 0-100 °C the CEMDATA data base is compatible with the GEMS default kernel database (GEMS version of Nagra-PSI 01/01 data base). Hence, the CEMDATA files comprise a specific extension to the GEMS kernel data base. A download in GEM-Selektor (Gibbs Energy Minimization) format is available.