Effect of polypropylene fibre on flexural properties of concrete composites containing fly ash and silica fume

The application of fly ash and silica fume in concrete composites by blending synchronously can improve the mechanical properties of concrete composites. However, the concrete composite becomes much brittle with the usage of fly ash and silica fume. Polypropylene fibre is often used to improve the ductility of concrete composites. This article discusses the effect of polypropylene fibre on the flexural properties of concrete composites containing fly ash and silica fume. Results reveal that the addition of polypropylene fibre can increase the flexural strength and decrease the flexural modulus of elasticity of the concrete composite containing fly ash and silica fume evidently. Furthermore, it is indicated that an increase in the fibre volume fraction leads to an increase in the flexural strength and a decrease in the flexural modulus of elasticity when the fibre volume fraction is not beyond 0.12 per cent. Polypropylene fibre seems to play an important role to improve the ductility of concrete composites containing fly ash and silica fume.