Title:
Effects of the Adsorption Characteristics of PCE on C3S Hydration
Author(s):
Ming Liu, Jing Chen, Yuxin Gao, Guangjun Zheng, and Jiaheng Lei
Publication:
Symposium Paper
Volume:
329
Issue:
Appears on pages(s):
213-224
Keywords:
Polycarboxylate-based superplasticizers; Tricalcium silicate; Surface chemistry; Cement and concrete; Thermal analysis.
DOI:
10.14359/51711216
Date:
9/26/2018
Abstract:
Adsorption characteristics of polycarboxylate-based superplasticizers (PCE) on tricalcium silicate (C3S) and its effect on the hydration of C3S were investigated. In addition, the morphology change of Ca(OH)2 in the presence of PCE was also examined. The results showed that the saturated adsorption amount of PCE on C3S is about 6~7 mg/g. Adsorption occurred on C3S surface as well as its hydrates and played an important role on hydration of C3S. Before the induction period, adsorption of PCE promote the hydration of C3S, while during induction period and reduction period, PCE retarded the C3S hydration. The morphology and size of Ca(OH)2 are found to be changed with the adsorption of PCE. The size of Ca(OH)2 crystals is about 0.5~1 μm, while it decreased to 0.2~0.5 μm after PCE modification. This study provides direct evidence for applying PCE to improve the mechanical and durability of concrete.
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