Anchorage effects of various steel fibre architectures for concrete reinforcement

This paper studies the effects of steel fibre geometry and architecture on the cracking behaviour of the reinforced concrete (SFRC), with the reinforcements being four types (5DHH, 4DHH, 3DHH-60 and 3DHH-35) of Dramix hooked end steel fibres with various hooked end shapes at two levels of 40 kg/m3 and 80 kg/m3 fibre doage. The test results show that the addition of steel fibres have little effect on the workability and compressive strength of SFRC, but the tensile peak loads, post cracking behaviour, residual strength parameters and the fracture energy of SFRC are closely related to the shapes of fibres which all increased with increasing fibre content. The 5DH steel fibre reinforced concretes have behaved in a manner of multiple crackings and more ductile compared to 3DH and 4DH ones, and the end-hooks of 4DH and 5DH fibres partially deformed in SFRC. In practice, 5DH fibres should be used for reinforcing high or ultra-high performance matrixes to fully utilize their high mechanical anchorage