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.