Title: Mechanical characterization of fiber reinforced floor screeds: Influence of glass fibers on shrinkage and cracking mechanisms
Author(s): Chelha, F.; Alam, S. Y.; Bendimerad, A.Z.; Loukili, A.
Publication: Symposium Paper
Appears on pages(s): 70-79
Keywords: Shrinkage; glass fibers; self-compacting mortar; floor screed; cracking
Self-compacting mortars and concretes for horizontal structures are cementitious mixtures
that are both fluid and homogeneous, with the particularity of flowing under the effect of their
own weight. Thanks to their homogeneous texture they offer the possibility of achieving good
quality of finishing and many such advantages become the reason for their applications
especially in slabs and floors.
However, self-compacting mortars or concretes show considerable shrinkage and cracking
problems when used in floors and slabs (Weiss et al., 1998). Because of their large moisture
exchange surfaces, the floor screeds are subjected to significant drying effects and in
particular plastic shrinkage. If the movements are restrained, the risk of cracking is high. In
this respect the use of fibers is a good alternative to using reinforcement bars and welded wire
mesh. Indeed on site a clear decrease in cracking caused mainly by the shrinkage can be
observed as soon as the fibers are incorporated in the screed.
This study is conducted to demonstrate the effectiveness and the effects of glass fibers on
the control of cracking phenomena due to shrinkage by determining their mechanisms of
action at young age. The study is carried out in two parts: Firstly, free shrinkage behavior is
analyzed in the fiber reinforced floor screed. Secondly, the restrained behavior at young ages
using recently developed uni-axial tensile testing machine is investigated.