Title:
Free and Restrained Shrinkage of Normal and
High-Strength Concretes
Author(s):
Ronit Bloom and Arnon Bentur
Publication:
Materials Journal
Volume:
92
Issue:
2
Appears on pages(s):
211-217
Keywords:
cracking (fracturing); high-strength concretes; shrinkage; sil-ica
fume.
DOI:
10.14359/9771
Date:
3/1/1995
Abstract:
Free and restrained shrinkage of concretes with and without silica fume were studied. A special uniaxial restraining rig was developed in which the stress required to prevent shrinkage from occurring could be monitored. Variables studied were the water-cement ratio (w/c), influence of silica fume, and exposure conditions (either exposure to drying environment immediately after casting or immediate sealing of the concrete after casting). The presence of silica fume increased free plastic shrinkage of the concrete and led to earlier cracking than a similar low-wlc concrete (0.33) with no silica fume. The sealed low water-binder ratio (w/b) concretes (0.33) developed considerable restraining (residual) stress, but none of them cracked. This stress was higher in the silica fume concrete.