ANALYSIS OF THE TIME-DEPENDENT VOLUME REDUCTION OF CONCRETE CONTAINING SILICA FUME

The use of silica fume (SF) to produce high-performance concretes is gaining acceptance in the construction industry. Concretes of compressive strength above 70 MPa with improved resistance to aggressive chemicals have been produced successfully using SF. The time-dependent volume reduction of concrete caused by moisture loss, known as drying shrinkage, is known to have a profound influence on cracking, long-term deflection and losses in prestressing. It is therefore necessary to have a clear understanding of these deformations in concrete containing SF in order to assess its long-term properties. In this Paper, results of an extensive test programme to evaluate the drying shrinkage of concrete containing different amounts of SF are presented and discussed. The results are analysed to help explain the mechanisms of drying shrinkage in concrete containing SF.