Affiliations: Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan | Institute of Technology, Shimizu Corporation, 3-4-17, Etchujima, Koto-ku, Tokyo 135-8530, Japan | Institute of Materials Structure Science, KEK, Tsukuba, Ibaraki 305-0801, Japan | Department of Materials Science and Engineering, Muroran Institute for Technology, Muroran 050-8585, Japan
Abstract: Structure refinements have been carried out on the pure tricalcium silicate (C3S) and the hydrated C3S with the D2O–C3S mass ratio, which is 0.5, using neutron powder diffraction (NPD). The multi-phase Rietveld analysis of the hydrated C3S revealed the coexistence with the Ca(OD)2 (trigonal phase) and the unhydrated C3S (triclinic one). The Ca(OD)2 phase was hardly observed on the NPD patterns in the first ∼6 h of hydration, while the several Bragg reflections of Ca(OD)2 appeared drastically from ∼6 to ∼24 h, and then the hydration reaction rate was gradually suppressed. We could apply the Avrami-model to the initial hydration reaction process of C3S.
