X-ray fluorescence method and thermal analysis of concrete prepared based on a share of fly ash and various chemical admixtures

Ondova M., Stevulova N., Meciarova L.

The utilization of fly ash in concrete as partial cement replacement has many benefits. It leads to increase of a binder´s amount and improves workability (pumpability, keepability and others) of fresh concrete, as fly ash behaves as a solid fluidifier. Application of fly ash in combination with a fluidifier is very effective, because it improves the workability of fresh concrete significantly. Regarding characteristics of lower class fresh concrete the main benefit of fly ash utilization with fluidifier is complement of fine binder, especially particles up to 0,25mm. At the same time, fly ash hinders segregation and flowing of very soft and liquid fresh concrete (cone consolidation 100 mm and more) contributes to the higher structure homogeneity and higher quality of concrete construction surfaces. The phases of hydrate created in pozzolanic reaction cause higher strength of fly ash mixtures, structure concretion, and finer porosity.
 However, results of our research of mechanical properties of fly ash – concrete composites by various chemical (plasticizers and aeration) additives showed deviations in the resulting strengths. The aim of this paper is monitoring of these deviations by the X-ray fluorescence method and thermal analysis and their subsequent evaluation.

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Ondova M. X-ray fluorescence method and thermal analysis оf concrete prepared based on a share оf fly ash and various chemical admixtures / Marcela Ondova, Nadezda Stevulova, Ludmila Meciarova // Вісник Національного університету "Львівська політехніка". – 2013. – № 756 : Теорія і практика будівництва. – С. 193–199. – Bibliography: 16 titles.