Alkali-Silica Reactivity Resistance of High-Volume Fly Ash Cementitious Systems

The role of high-volume ASTM Class F fly ash (58% by mass of cement) in reducing expansion caused by alkali-silica reaction was investigated. A series of modified ASTM C1260 tests were performed with three different concentrations of NaOH solution and over an extended test period of 28 days; a reactive siliceous fine aggregate was used. Test results confirm that replacing 58% of portland cement (by mass) with high-volume fly ash in a cementitious system significantly helps control expansion caused by alkali-silica reaction.