Influences of alkali oxides doping on the crystal structure, defects and hydration behavior of tricalcium silicate C_3S were investigated by X-ray powder diffraction with the Rietveld method, inductively coupled plasm...Influences of alkali oxides doping on the crystal structure, defects and hydration behavior of tricalcium silicate C_3S were investigated by X-ray powder diffraction with the Rietveld method, inductively coupled plasma optical emission spectroscopy, thermoluminescence and isothermal calorimetry. All the samples were stabilized as T1 form C_3S. Changes in the crystal structure of C_3S could mainly be monitored by changes in lattice parameters, which were closely correlated with the incorporation concentration and substitution types of alkalis. Although alkalis were incorporated at trace level in C_3S, the thermoluminescence and hydration behavior of C_3S were significantly influenced. Initial hydration activity was dramatically increased and highly related to the intensity of the irradiation-induced thermoluminescence peaks at low temperatures due to their direct correlation with defects. The oxygen vacancy sites resulting from the substitution of alkalis for Ca could readily account for the acceleration of the initial hydration of C_3S.展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51302256 and 51672260)the Synergetic Innovation Center for Advanced Materials and State Key Laboratory of Silicate Materials for Architectures(Wuhan University of Technology)
文摘Influences of alkali oxides doping on the crystal structure, defects and hydration behavior of tricalcium silicate C_3S were investigated by X-ray powder diffraction with the Rietveld method, inductively coupled plasma optical emission spectroscopy, thermoluminescence and isothermal calorimetry. All the samples were stabilized as T1 form C_3S. Changes in the crystal structure of C_3S could mainly be monitored by changes in lattice parameters, which were closely correlated with the incorporation concentration and substitution types of alkalis. Although alkalis were incorporated at trace level in C_3S, the thermoluminescence and hydration behavior of C_3S were significantly influenced. Initial hydration activity was dramatically increased and highly related to the intensity of the irradiation-induced thermoluminescence peaks at low temperatures due to their direct correlation with defects. The oxygen vacancy sites resulting from the substitution of alkalis for Ca could readily account for the acceleration of the initial hydration of C_3S.
