Title: Influence of Exposure of Concrete to Salt Upon Expansion Due to ASR

Author(s): D. W. Hobbs

Publication: Symposium Paper

Volume: 154

Issue:

Appears on pages(s): 489-508

Keywords: aggregates; alkali-aggregate reactions; expansion; fly ash; portland cement; salts; slags; Materials Research

DOI: 10.14359/966

Date: 5/1/1995

Abstract:
Presents results of expansion tests carried out on concretes immersed in 1/10-M and 1-M sodium chloride solutions. The concretes were prepared using two reactive aggregates, cristobalite and a natural aggregate from the southwest of the U. K. Tests were carried out both at alkali levels which were known to induce expansion due to alkali-silica reaction (ASR) and alkali levels which would not normally induce expansion due to ASR. The concretes were, at the ages of one, three, and six months, immersed in a sodium chloride solution. The concretes were stored at 38 C, 20 C, and externally. For the concretes containing the natural aggregate, it was shown that immersion in a 1-M salt solution had no major adverse effects upon long-term expansion. This is attributed to the low available reactive silica content within the concretes. In the case of concretes containing cristobalite, it was shown that the immersion in 1-M salt solution had an adverse effect upon long-term expansion. This is attributed to the high available reactive silica content of the concrete.