The objective of this study is to propose a rheological model for a self-compacting concrete (SCC) on a reduced scale in which a mobile (with 4 vanes) rotating at an imposed speed is immersed. This ...model allows to describe the rheological behaviour of concrete (at full scale) and to acquire its intrinsic parameters, namely the yield stress and the plastic viscosity. The validation of this approach is established first of all from the realization of six self-compacting concretes (at the real scale). The intrinsic rheological parameters given by their reduced concretes confirm their self plasticity by referring to the rheological results obtained with three other rheometers of international references. Indeed, a very good correlation is obtained between the slump flow of these six SCC and the yield stress of their reduced concretes. Moreover, a design of experiments with three variables is used to demonstrate that this approach is suitable for providing a mathematical model of the intrinsic rheological parameters (yield stress and viscosity) of SCC. The results showed that the yield stress is governed by the interactions (paste-superplasticizer) and (paste-aggregate) while the viscosity is exclusively governed by the paste.
The purpose of this study is to formulate a steel fibre reinforced self-compacting concrete (SFSCC) that has optimal rheological and mechanical properties, using marble powder as an addition and ...partial substitution to cement. The design of experiments method (DOE) was used to analyse the effect of fibre dosage (%f), paste volume (V
p
) and the gravel/sand ratio (G/S) on the SFSCC. A concrete rheometer is used to quantify the intrinsic rheological parameters. The rheological results of the SFSCC show that the flow capacity decreases with increasing fibre dosage. By against the increase in the volume of the paste (V
p
) and the (G/S) ratio decreases the yield stress to give better performance to flow. The plastic viscosity is governed exclusively by the volume of the paste. Mechanical results showed that the volume of the paste has a significant influence on the flexural strength as well as the compression strength. Moreover, significant improvement in flexural strength is recorded when the three parameters (%f, V
p
and G/S) increase. Also, the ductility of SFSCC increases with increasing fibre dosage, while the compressive strength is little affected by the latter.
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