Effects of thaumasite formation on the performance of Portland-limestone concrete stored in magnesium sulfate solution

Abstract

The influence of thaumasite formation on the performance of Portland-limestone cement concrete stored in magnesium sulfate solution was studied. The experimental results show that the deterioration of Portland-limestone cement concrete is higher than that of Portland cement concrete. The more the content of limestone, the more serious the deterioration of concrete, and also the lower the temperature, the earlier the deterioration of concrete. Thaumasite was detected to form in the Portland-limestone pastes when stored in 10wt% MgSO₄ solution at 3–10°C and it was easy to form at lower temperatures.

Keywords

concrete / sulphate attack / attack mechanism / thaumasite / ettringite

References

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