Alite-Belite-Ye'elimite cements: effect of dopants on the clinker composition and properties

ABSTRACT: Clinkers with alite-belite-ye´elimite (ABY) are considered as eco-friendly cements. Clinkering (2 Kg) of two types of ABY clinkers was optimized: standard-ABY, with CaF₂ and ZnO as dopants (32.6 wt% alite, 30.4 wt% b-belite and 15.6 wt% ye'elimite) and αABY, with CaF₂, ZnO, B₂O₃, Na₂O (14.4 wt% alite, 37.1 wt% b-belite, 18.5 wt% α'_H-belite and 7.5 wt% ye'elimite). Zn and F were mainly incorporated in alite and ferrite, while S sulfur was mostly incorporated into Fluor-ellestadite, ye’elimite and, in lower percentages, in belite and ferrite, determined by EDS semi-quantitative. The effect of dopants on the hydration of the cement mortars has been tested. Thus, standard-ABY develops 29.9 MPa compressive strengths at 1 day while αABY does 16.8 MPa, mainly due to the higher amount of alite of the former. The presence of α’_H-belite in αABY increases mechanical strengths at 28 days of hydration from 44.7 MPa of standard-ABY to 74.9 MPa.