Title: Alkali-Aggregate Reaction--The Bogeyman of Concrete

Author(s): R. N. Swamy

Publication: Symposium Paper

Volume: 144

Issue:

Appears on pages(s): 105-140

Keywords: alkali-aggregate reactions; alkalies; beams (supports); cement-aggregate reactions; coatings; columns (supports); durability; cracking (fracturing); mineral admixtures; modulus of elasticity; moisture; pozzolans; reinforcing materials; slabs; stiffness;

DOI: 10.14359/4394

Date: 3/1/1994

Abstract:
The mention of alkali-aggregate reactivity (AAR) often conjures up visions of an intolerable and unremediable cancerous disease to which all concrete is subjected. It generates a lack of precise and thorough understanding of the phenomenon and strikes fear in the minds of concrete technologists, engineers, and the public alike. The aim of this paper is to put the phenomenon of AAR in a proper perspective in relation to its mechanisms, effects, and influences. An attempt is made to unravel the mysteries of AAR and the myths and mythologies associated with it. Paper describes the behavior and method of operation of the phenomenon, and assesses its impact on the engineering properties of concrete and structural performance of load-bearing members. It is shown that it is possible to check, and indeed contain, the effects of the attack both in new construction and in existing structures.