Mixing of concrete or mortars: Dispersive aspects

This article describes an experimental methodology offering mixing efficiency criteria for granular materials in terms of their dispersion capability. This methodology is based on the analysis of the dispersion kinetics of colored, cohesive, tracer particles that progressively disagglomerate during stirring. The effects of certain critical parameters such as the mixer speed and the type of mixer are described. In terms of the mix design, the contribution of the largest particles to the dispersion kinetics, and therefore to the mixing efficiency, is highlighted. A simple comparison of the mixing efficiency of mixer/mix design/procedure sets is finally provided for such cementitious granular materials.