Bonding Behaviour of Steel Fibres in UHPFRC Based on Alkali-Activated Slag.

The mechanical performance of fibre-reinforced ultra-high-performance concrete based on alkali-activated slag was investigated, concentrating on the use of steel fibres. The flexural strength is slightly higher compared to the UHPC based on Ordinary Portland Cement (OPC) as the binder. Correlating the flexural strength test with multiple fibre-pullout tests, an increase in the bonding behaviour at the interfacial-transition zone of the AAM-UHPC was found compared to the OPC-UHPC.

Effect of Fibre Material and Fibre Roughness on the Pullout Behaviour of Metallic Micro Fibres Embedded in UHPC.

The use of micro fibres in Ultra-High-Performance Concrete (UHPC) as reinforcement increases tensile strength and especially improves the post-cracking behaviour. Without using fibres, the dense structure of the concrete matrix results in a brittle failure upon loading. To counteract this behaviour by fibre reinforcement, an optimal bond between fibre and cementitious matrix is essential.