Rheological properties of concrete with manufactured sand : A multi-level prediction

Conventional rheological predictions of concrete were mostly developed based on spherical aggregate assumptions whereas the particle shape of irregular aggregate significantly influences the rheological properties of concrete. In this study, rheological properties of concrete with manufactured sand (MS) are predicted concerning the particle shape of aggregate based on a multi-level biphase assumption. The relative plastic viscosity and relative yield stress at each level are demonstrated to present power-law relationships with the relative thickness of the corresponding suspending media. The proposed models are proved with high accuracy and robustness for predicting the rheological properties of mixtures with MS and coarse aggregate that have various particle shapes and particle size distributions. Based on the proposed predictions, the influences of particle shapes of MS and coarse aggregate on the rheological properties of mixtures can be represented by their effects on the relative paste film thickness (R_PFT) and relative mortar film thickness (R_MFT), respectively. The proposed multi-level prediction lays the foundation of mix proportioning of concrete with irregular aggregate according to the specified rheological requirements. © 2022 Elsevier Ltd. All rights reserved.