The early hydration of OPC investigated by in-situ XRD, heat flow calorimetry, pore water analysis and 1H NMR: Learning about adsorbed ions from a complete mass balance approach

Abstract

In-situ XRD, heat flow calorimetry, pore water analysis and 1H NMR were used in order to gain more detailed understanding for cement hydration within the first hours of hydration. All methods used show very satisfying accordance. All information gained from the different methods were used in order to calculate absolute mass balance for several ions in order to get an idea about ionic reservoirs adsorbed on surfaces during cement hydration. Sulfate and aluminum adsorption show impact on sulfate depletion, calcium does not.