MATHEMATICAL EVALUATION OF DELETERIOUS PROCESSES OF FLY ASH-BASED CONCRETE IN PIPELINES

Concrete performs well when exposed to various atmospheric conditions, water, soil, and many other chemical exposures. However, some chemical environments or even water can deteriorate high-quality concrete. Paper considers the usefulness of current fly ash concrete technology and prevention techniques, and advances a new approach for making concrete resist the deleterious effects of corrosion. This paper is focused on study of the durability of concrete materials based on two types of fly ashes which substitute 5 wt. % of cement in concrete mixture. Mathematical evaluation using correlation analysis was applied for assessment of deterioration of the concrete samples with fly ash of different origins. Experiment was done by measurements of elementary leached-out ions concentration (Ca, Si, Fe, Al, Cu and Mn) and subsequently correlation analysis between the ions each other (in the same type of fly ash or between different types of fly ash respectively) and also correlation between ions concentrations and pH values of leachate. The correlation coefficient showed different mechanism of calcium and silicon ions leaching when comparing the concrete samples with fly ash from brown coal burning and samples with fly ash from black coal burning.

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