Influence of fibre geometry and matrix maturity on the mechanical performance of ultra high-performance cement-based composites

This paper concerns an experimental study of the influence of the geometry of the longest steel fibre and of the matrix maturity on the mechanical behaviour of an ultra high-performance multi-scale fibre reinforced cement-based composite. The following conclusions can be drawn: • Ultra high-performance cement matrix with a very low water/binder ratio continues to mature and undergoes additional densification over time. This tendency leads to a significant increase of the material modulus of rupture as the age of the material advances. • In a very dense matrix, the total number of fibres in the matrix and the specific surface of the fibre are more important parameters than the existence or not of hooks at the fibre ends. • Twisted steel fibres lead to a better material mechanical performance than steel fibres with hooks at their ends.