Numerical modelling of flow performance of fresh concrete considering rheological characteristics

The flow performance of concrete has a significant impact on the workability during the fresh stage, as well as the mechanical strength and durability after hardening. In this study, a three-dimensional numerical model for fresh concrete is developed to investigate the flow properties, including flowability, passing ability, and filling ability, by means of L-box and V-funnel tests. Corresponding experiments are carried out to validate the reliability of the presented model. Moreover, parametric investigations are performed to analyse the influence of relevant factors. The results show that the model predictions based on the Herschel-Bulkley model are more accurate compared to the Bingham model, indicating that the role of nonlinear rheological characteristics in the flow performance of fresh concrete needs to be properly considered. Both tL and tV are positively correlated with the power-law exponent, yield stress, and consistency index of the concrete mixture, whereas they are negatively correlated with the apparent density. The findings of this study can provide a deeper understanding of the underlying mechanism behind the flow behaviour of fresh concrete from a rheological perspective.