Mechanical performance of flow-induced self-compacting steel fibre-reinforced concrete used for structure of hydraulic works

Steel fibre inclusion into self-compacting concrete produces important benefits, mainly on the residual load-bearing capacity. These improvements depend significantly on the dispersion and orientation of the fibres. This paper focuses on mechanical performance of flow-induced self-compacting steel fibre-reinforced concrete (SCSFRC) used for structure of hydraulic works. Two types of casting manners were used for preparation of SCSFRC beams. The first is casting at the middle of the mould and let the mixture to spread to both sides of the mould (Type I), and the second is casting from the one side of the mould and let the mixture flowing to the other side (Type II). Under four-point bending test, flexural behaviour of SCSFRC beams showed that in terms of first-cracking strength both of beam types (Type I and Type II) resulted in the similar outcomes. However, the maximum strength of SCSFRC obtained from the beam type II was 12.5% higher than that from the beam type I. In addition, the Type II also outperformed the Type I in terms of post-cracking flexural behaviour. This fact was mainly due to the better fibre alignment in the Type II in comparison with the Type I, resulting better mechanical performance.