A new accelerated method for determining the potential alkali-carbonate reactivity

Many kinds of carbonate aggregates with different chemical compositions, structure, and geological characteristics have systematically been investigated. This research deals with chemical components and mineral analysis, petrographic examination of the aggregates, the dynamics of alkali-carbonate reaction with different cements, alkali contents, and particle sizes. A new method for evaluating the potential alkali-carbonate reactivity has been proposed according to the results, in which the major test factors include 1.5% Na₂O_eq. of alkali content, 1 M NaOH solution, 0.3 water-to-cement ratio, 5-10 mm particle size, and 4 weeks of test period at 80 °C. The results using this new method has also been compared with that of the performance of concrete structures in China.