Title: Calcium Sulfoaluminate-Based Expansive Admixtures A Review

Author(s): W. L. Repette and N. P. Mailvaganam

Publication: Symposium Paper

Volume: 217

Issue:

Appears on pages(s): 177-194

Keywords: calcium sulfoaluminate; concrete; expansive admixture; high alumina cement; shrinkage

DOI: 10.14359/12913

Date: 9/1/2003

Abstract:
Shrinkage is an inherent characteristic of cementitious materials and its adverse effects can compromise the mechanical integrity and durability of concrete. The use of construction joints, restraining reinforcement and special cements is not entirely effective in preventing the development of damaging cracks. Current methods of offsetting shrinkage involve the use of shrinkage compensating cements (SCC) and expansion producing calcium sulfoaluminate (CSA) based admixtures. The most important limitations to the use of these materials are rapid set, loss of workability and the amount and timing of the expansion produced. A recently developed new type of CSA admixturebased on calcium aluminate hydrates-has proved to be effective in compensating the shrinkage produced in medium strength (30-35 Mpa) concrete. This paper reviews the basic characteristics of currently available shrinkage compensating materials. Details are given on composition, mode of action, use and performance of the different admixtures.