Title: Development of a Canadian Specification for Silica Fume

Author(s): H. L. Isabelle

Publication: Symposium Paper

Volume: 91

Issue:

Appears on pages(s): 1577-1588

Keywords: alkali-aggregate reactions; chemical analysis; concretes; fineness; physical properties; portland cements; pozzolans; shrinkage; silica; specifications; tests; General

DOI: 10.14359/1783

Date: 2/1/1986

Abstract:
Silica fume has been used commercially for five years in Canada, particularly in the province of Quebec where most of the material is produced. Field problems such as plastic shrinkage that were experienced in the early stages and the distinct nature of this pozzolan caused some concern among prospective users who, while recognizing the unique properties and potential of silica fume, were hesitant to specify it. Added to their apprehension was the unavailability of a recognized standard. These considerations prompted the Concrete Materials and Construction Committee of the Canadian Standards Association (CSA) to develop a specification for silica fume. Findings from research by the University of Sherbrooke, Quebec, and the Canadian Center for Mineral and Energy Technology, Ottawa, Canada, provided input for the new specification which is now part of CSA Standard A23.5, Supplementary Cementing Materials and Guidelines for their Use in Concrete. During the preparation of the specification, close contact was maintained with Committee 226 and ASTM Committee C618 which are in the process of preparing a state-of-the-art report and a specification, respectively. The Canadian specification, believed to be the first of its kind in the world, will eventually be updated particularly as regards to the ASTM C 311 methods of tests which were originally developed for pozzolans that are not as finely divided as silica fume.