Materials Research Engineer, National Bureau of Standards, Gaithersburg, MD
Professor, Purdue University, West Lafayette, IN
Pages: 15 Published: Jan 1986
In order to better understand the factors controlling alkali-silica reaction, a study was carried out to show if the distribution of alkalies among the cement minerals influences the expansion of mortar containing reactive aggregate. The approach was to determine the distribution of alkalies in four high-alkali portland cements, and to measure expansion of mortar bars prepared using these cements and reactive aggregates. In some cases, differences were observed in both the ultimate level and the early rate of expansion for cements differing in distribution of alkalies. The differences were substantial with opal as the reactive constituent. Cements richer in soluble alkali-sulfate phases appeared to show greater levels and rates of expansion. The results demonstrate that the specific distribution of alkalies among the cement minerals affects the expansion due to alkali-silica reaction.
alkali, alkali-silica reaction, cement mineralogy, concrete, mortar bar expansion, portland cement, reactive aggregate, water-soluble alkali
Paper ID: STP18462S