Preparation and fracture properties of different types of aligned steel fiber reinforced concrete

The orientation of steel fibers influences the fracture properties of steel fiber reinforced concrete (SFRC) structures.In order to enhance the fracture properties of SFRC structures, the magnetic field method was used to adjust the fiber orientation to maximize the reinforcing efficiency of steel fibers.By this method, the unidirectionally aligned steel fiber reinforced concrete (1D-ASFRC) was manufactured.Furthermore, the two-dimensionally aligned steel fiber reinforced concrete (2D-ASFRC), annularly aligned steel fiber reinforced concrete (AASFRC) and full-field aligned steel fiber reinforced concrete (FASFRC) were prepared based on this fiber orientation adjustment technique, with the aim of promoting the application of ASFRC in various structural forms such as pipe segments, slabs, pavements, bridge decks, and open-hole structures.Subsequently, the advantages of ASFRC in enhancing fracture properties were examined by comparing its performance against that of conventional SFRC specimens.The results indicated that compared to SFRC, both fracture toughness and fracture energy were significantly improved in ASFRC.This implies that using less fibers in ASFRC structures can ensure the fracture properties equivalent to that of SFRC structures.Finally, an investigation into the reinforcement mechanism of ASFRC was conducted from the perspective of fiber distribution characteristics and numerical simulation.