Autoclave test parameters for determining alkali-silica reactivity of concrete aggregates

The objective of this study was to determine appropriate values for alkali loading, autoclaving temperature, and autoclaving duration for alkali-silica reaction testing of aggregates in mortar bars. Alkali loadings between 0.52 and 4.5%, autoclaving temperatures from 105 to 130 °C, and autoclaving durations between 5 and 48 h were used. A total of 72 tests involving eight aggregates of various mineralogies and reactivities were performed. Appropriate values for test parameters were found to be: alkali loadings between 3.0 and 3.5%, autoclaving temperatures between 120 and 130 °C, and autoclaving durations between 5 and 12 h for mortar bars, regardless of aggregate type.