Simplified prediction of the time dependent deflection of SFRC flexural members

It is well known that the inclusion of steel fibres into a concrete matrix has the potential to improve both the serviceability and strength characteristics of reinforced concrete. As a result of decades of academic interest into the material, design provisions for flexural strength, shear strength and short-term serviceability have been incorporated into international codes of practice. However, available design guidelines typically contain little or no guidance for engineers to confidently predict the long-term behaviour of structures manufactured with steel fibre reinforced concrete (SFRC). This limits the full utilization of the material in design practice. This paper presents a simplified model, suitable for design, that can reliably predict the effects of creep and shrinkage in SFRC members containing conventional reinforcement which are subjected to a sustained in-service flexural load. Predictions of the proposed model are compared to available data in the literature and are shown to correlate well.