Evaluation of steel fiber orientation in slab elements induced during casting with self-compacting concrete

Abstract

The use of self-compacting concrete (SCC) combined with fiber reinforced concrete (FRC) has been the subject of several recent studies. The combination of the fluidity of the SCC with the use of fiber increases the possibility that, during the casting process, there is preferred orientation of the fibers, even in the case of slab elements. This could provoke an enhancement or a loss in structural performance, once the post cracking strength of FRC relies on the positioning and orientation of the fibers. Because of this, the development of a methodology is needed in order to allow the assessment of this condition. The use of special test methods, as the inductive test, may be a useful tool to help to understand the influence of the casting conditions in fiber orientation. However, there are not many studies focused on the parameterization of this condition in slab elements. The present study aims to use the inductive test method in cubic cores sawn from a slab made of steel fiber reinforced self-compacting concrete. As result, the inductive method was able to assess the variation in the fiber concentration and the fiber orientation in each core. The use of the individual cubes measured results turn possible to draw flow lines that point to the influence of the casting in the preferred fiber orientation and concentration.

Keywords
Fiber orientation; Inductive method; Slabs; Fiber reinforced self-compacting concrete