Sustainable development of ultra-high performance fibre reinforced concrete (UHPFRC): towards to an optimized concrete matrix and efficient fibre application

This paper addresses the sustainable development of Ultra-High Performance Fibre Reinforced Concrete (UHPFRC). In general, based on theoretical and practical points of views, two strategies are employed here: 1) optimized design of the UHPFRC matrix based on modified Andreasen & Andersen particle packing model and appropriate application of substitutive materials; 2) efficient improve the fibre efficiency based on an optimized casting method. The obtained experimental results show that by utilizing the improved packing model and appropriate substitutive materials, it is possible to design a dense UHPFRC skeleton with relatively low binder amount, and the embedded CO₂ emission of the designed UHPFRC matrix can be effectively reduced. Moreover, based on the adjustment of fresh UHPFRC flowing parameters (such as flowing direction, flowing distance), the fibres orientation can be controlled, and an optimized UHPFRC with better mechanical properties can be obtained. Additionally, when the particle packing model, substitutive materials and controlled casting method are well utilized together, an optimized UHPFRC with low environmental impacts and high materials efficiencies can be obtained, which could promote a cleaner construction production in the near future.