Role of C-F-S-H/PCE nanocomposites on the hydration of Portland cement with varying gypsum levels

Abstract

This study delves into the role of C-F-S-H/PCE (calcium-ferrite-silicate-hydrates/polycarboxylate ether) nanocomposites on the cement hydration with varying gypsum levels. It is found that the addition of C-F-S-H/PCE nanocomposites simultaneously promotes the dissolution of cement clinker and gypsum during early hydration. What’ more, the early hydration is further enhanced notably by C-F-S-H/PCE nanocomposites at moderately higher gypsum level without compromising the long-term compressive strength. It merits attention that the compressive strength of cement paste emerges as a factor intricately interwoven with not only its microstructure but also the content of AFt (ettringite) it harbors. Anyway, in the presence of the C-F-S-H/PCE nanocomposites, the faster depletion of gypsum leads to an earlier formation of AFm (monosulfoaluminate) whereas the morphologies of various hydration products remain unaffected. The findings demonstrate that the addition of C-F-S-H/PCE nanocomposites increases the demand for gypsum in cement and provide insights into the production of cement and concrete using seeding materials.