- Author
-
Struble, L. J.
- Title
- Alkali-Silica Reaction in Concrete. Final Report. November 1983-January 1985.
- Coporate
- National Bureau of Standards, Gaithersburg, MD
- Sponsor
- National Science Foundation, Washington, DC
- Report
-
NBSIR 85-3116
March 1985
- Distribution
- Available from National Technical Information Service
- Contract
- NSF-CEE82-10791
- Keywords
-
concretes; alkalies; silicon dioxide; portland cements; aggregates; cracks; mortars (material); tests; chemical reactions
- Abstract
- Reaction in concrete between alkalies from the cement and reactive silica in the aggregate may cause expansion and cracking, and occasionally may cause significant weakening of the structure. The objective of this program is to determine whether there is any influence of the alkali mineralogy in the cement on the expansion of mortar due to alkali-silica reaction. The experimental approach consisted of determining the distribution of alkalies within a group of commercial portland cements with a variety of alkali mineralogies, and measuring expansion of mortar bars prepared using these cements and various reactive aggregates. In some cases, differences were observed in both level and rate of expansion for cements differing in alkali mineralogy. The differences were substantial with cements high in alkali and with opal as the reactive constituent. The results support the authors hypothesis that the specific alkali mineralogy of the cement affects the expansion due to alkali-silica reaction.