Early Stage Microstructure Development of Cement Paste Modified by Crystalline Admixture

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The hydrophobicity enhancement of structural materials is a contemporary topic of discussion. This paper deals with the effect of crystalline admixture (CA) on the microstructure of the cementitious composite in first four weeks after the production. Previous investigation was performed on the referential specimens consisting only from pure cement. The samples of pure CA and cement modified by 1% of CA with same w/c ratio were examined and compared in this paper. By investigation of these materials on the micro-scale in the time, it is possible to identify the development of the microstructure of each and determine the impact of the modification. For this purpose, backscattered electrons microscopy (BSE) with energy-dispersive X-ray spectroscopy (EDX) was used for phase analysis as well as instrumental nano-indentation to obtain the micro-mechanical properties. The presented results show the evolution of mechanical properties and microstructure in time and the impact of the crystalline admixture on modified cement.

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92-99

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December 2016

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