Hydration and Properties of Cement in the Belite-Ye′elimite-Ternesite System

Energy consumption and carbon emissions are lower in the production of belite-ye′elimite-ternesite (C(2)S-C(4)A(3)$-C(5)S(2)$, BYT) clinker than Portland cement (PC) clinker. BYT cement can combine the early strength of CSA cements and the durability of belite cements. X-ray diffraction, mercury intrusion porosimetry, isothermal conduction calorimetry and scanning electron microscope were conducted to investigate the hydration process of BYT cement. The hydration products of BYT cement include mainly ettringite, strätlingite and some amorphous AH(3) (aluminum hydroxide). Ternesite did prove an early reactivity in BYT cement. The reaction of ternesite with AH(3) occurs on the surface of ternesite. Ternesite delays the second heat flow peak of ye′elimite. The strength of BYT cement containing 10% ternesite in the prepared clinker exceeds that of other cement at all ages.