Effect of gypsum on hydration properties, composition and kinetics of low carbon belite-ye'elimite-Q phase-ferrite clinker

In this study, a new low-carbon clinker, belite-ye'elimite-Q phase-ferrite (BYQF), was produced and hydrated with and without gypsum at 8 %, 15 % and 30 % mass concentrations. The results show an optimum compressive strength of 122 MPa (90 days) with 30 wt% gypsum addition. The gypsum content determines the development of the compressive strength, which can be increased by 30 % to 105 % due to the change in gypsum content compared to BYF clinker. Gypsum inhibited strength decrease at late stage and shortened the induction period. Although 30 wt% gypsum reduced the dissolution rate of C2S and C4AF, it increased ettringite and AH3 content in the middle and late stages, which reduced porosity and promoted strength growth. Based above results, BYQF shows outstanding performance and is expected to be used as a sustainable building material.