A case study on the spatial variability of strength in a SFRSCC slab and its correlation with fibre orientation

Abstract

This paper presents the results of an experimental investigation into the effects of the fibre orientation and the concrete casting method on the flexural strength and fracture toughness of steel fibre reinforced self-compacting concrete (SFRSCC). A destructive four-point bending testing is used to measure the flexural strength at the main cracking, the accepted mean post-cracking loading, and the energy absorption capacity (toughness) of the concrete. It is shown that a favourable fibre orientation increases flexural strength up to 25%, the accepted mean post-cracking loading up to 65%, and the toughness up to 65% for the specific concrete mixture and concrete beams used. The presented results and analysis demonstrate the importance of the spatial fibre orientation and distribution on the final strength and durability of hardened concrete. The main findings and conclusions of this paper can also be extended to other fibre reinforced composite materials.

Keywords

• open pour concrete casting
• material strength
• free-surface flow
• fibre orientation
• four-point bending test
• concrete reinforcement
• concrete cracking
• crack control
• structural concrete elements.