Development of Ultra-High Performance Fibre Reinforced Concrete (UHPFRC): Towards an efficient utilization of binders and fibres

• A method to efficiently produce UHPFRC is proposed.
• UHPFRC is produced with relatively low binders and fibres content.
• UHPFRC with ternary fibres is designed and produced.
• The effect of hybrid fibres on the flexural toughness of UHPFRC is studied.
• The standards for calculating the UHPFRC toughness are evaluated.

This paper presents a method to develop Ultra-High Performance Fibre Reinforced Concrete (UHPFRC). Towards an efficient utilization of binders and fibres in UHPFRC, the modified Andreasen & Andersen particle packing model and the hybridization design of fibres are utilized. Particularly, the UHPFRC with ternary fibres is appropriately designed and tested. The flowability, mechanical properties and flexural toughness of the designed UHPFRC are measured and analyzed. The results show that, based on the optimized particle packing and hybrid macro and micro fibres, it is possible to produce UHPFRC with a relatively low binder amount (about 620 kg/m3) and low fibre content (Vol. 2%). Moreover, due to the mutual effects between the utilized fibres, the hybrid fibre reinforced UHPFRC shows an improved flowability and better mechanical properties. Nevertheless, the flexural toughness of UHPFRC is dominated by the hooked steel fibres. Due to the specific characteristics of UHPFRC, the JSCE SF-4 standard is found more suitable than ASTM C1018-97 to be used to evaluate the flexural toughness of UHPFRC.