THE EARLY AGE STUDY OF CEMENT HYDRATION BY IN-SITU SYNCHROTRON X-RAYS DIFFRACTION
Keywords:
Wide angle X-ray scattering (WAXS), X-ray diffraction (XRD), cement hydrationAbstract
The x-ray diffraction technique is normally used to determine cement hydration products such as ettringite (AFt), monosulfate (AFm), and portlandite (CH). The hydrated samples have to be prepared in dry powder and the cement hydration reaction has to be stopped at a specific time. It is not practical to study the hydration products at a very early age. To overcome this limitation, the in-situ wide angle x-ray scattering technique (WAXS) was used to investigate cement hydration. Because of the high intensity of synchrotron x-rays, the measurement time was shortened. This enabled the study of cement hydration at a very early age by the WAXS technique which gave valuable information on the rate of formation and depletion of the cement hydration products at a very early age and an understanding of the cement’s properties such as workability and early compressive strength.
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