Dehydration Process of Calcium Silicate Hydrate during Heating in the Air

Abstract

Investigation on the continuous dehydration process of calcium silicate hydrate with C/S 1.5 during heating in the air was carried out. Results showed that the heating at 200°C of C-S-H resulted in decreasing basal spacing from 1.2 nm to 1.0 nm, and the basal spacing disappeared as the temperature raised to 400°C. Small amount of the dehydrated calcium silicate hydrate, portlandite and calcite were detectable in the heated sample at 400°C. The phases in the samples heated at 500°C and 650°C are β-C2S, quartz, and calcite. At 800°C and 900°C, α′-C2S, β-C2S, and quartz are main phases in the heated sample.

X-Ray Diffraction Comparison Study of Binders Derived from Pure C₃S and Portland Cement Paste

“…The β-C2S polymorph begins to form when temperatures exceed 800°C, while the α'-C2S polymorph is produced at temperatures below this threshold [16][17][18][19]. In contrast to the findings of Lu et al [20] 's study, which demonstrated the formation of the beta phase in synthesized C-S-H samples that were heated to temperatures of 500°C and 650°C, while the presence of both α'-C2S and β-C2S was observed in samples that were heated to 800°C.…”

Effective Utilization of Waste Glass as Cementitious Powder and Construction Sand in Mortar

“…There was a significant loss of weight in different temperature ranges, that is, 120-150 • C for water loss, 440-460 • C for decomposition of Ca(OH) 2 , 700-730 • C for decomposition of CaCO 3 , and 1200-1400 • C for decomposition of sulphate [57], respectively [58][59][60]. The entire process of heating went with the decomposition of calcium-silicate-hydrate (CSH) gel [61,62].…”