Influence of basalt-polypropylene fibres on fracture properties of high performance concrete

The aim of this research is to establish the fracture properties of high performance concrete (HPC) containing hybrid - basalt (B) and polypropylene (P) fibres. The experimental investigation consisted of tests on cubes, beams and notched prismatic specimens made of plain HPC and fibre reinforced HPC with 1% and 2% of basalt and/or polypropylene fibres. Extensive data on the compressive and tensile splitting strength, flexural behaviour, as well as fracture energy are determined and analyzed. The experimental investigations show that HPC with hybrid B/P fibres display a more ductile behaviour compared to that of plain HPC. The results of the bending tests revealed extended post-peak softening behaviour. The shape of the descending branch depended on the mechanical properties of the fibres, and volume content used. The results illustration the positive effect of high modulus basalt and low modulus polypropylene fibres on HPC fracture energy growth. Moreover the results indicate that a combination of fibres may contribute more effectively to increasing the flexural strength, flexural toughness and fracture energy than using a single type of fibre.