Relationship between workability and mechanical properties of fibre-reinforced self-consolidating mortar

Abstract

Non-uniform distribution of fibres and also instability of mixture tend to degrade as well as introduce undesirable variability into the mechanical properties of the mixture. This study investigates the effects of aspect ratio and volume fraction of polypropylene fibre on fluidity, flow time, stability and mechanical properties of fibre-reinforced self-consolidating mortars (FRSCMs). The obtained results indicate that stability and segregation resistance of ordinary self-consolidating mortars plays a significant role in the fluidity, stability and fibre dispersion of fibrous mortar. Moreover, this paper suggests critical and dense fibre factors to show the variability of fluidity, stability and also mechanical properties of mixtures. The results show that, for a water/cement ratio of 0·4 and fibre factor less than 90, fibres formed networks, in which aggregates are efficiently confined and so result in more segregation resistance of mixtures. On the other hand, for mixtures with a fibre factor above the dense fibre factor, non-uniform distribution and clumping of fibres occur, leading to a poor mechanical behaviour. The combined fluidity and stability data allow an improved description of the processes, which are responsible for segregation and fibre clustering in FRSCM.