How quarry waste limestone filler affects the rheological behavior of cement-based materials

The main objective of this work is to highlight experimentally the effect of quarry waste limestone fillers (LF) on the rheological properties of concrete. All mixtures were made with water-to-cement ratio (W/C) of 0.50. The method adopted based on the rheological behavior of concrete incorporating LF as a partial substitute for sand in multi-scale systems (concrete, mortar, grout and LF suspension). The replacement ratio of sand by LF ranged from 0% to 20% (by weight of sand) in concrete and mortar. Whereas, the addition of LF varied from 0% to 60% (by weight of cement) in cement grout. The rheological behavior of concrete and mortar was modeled by the Bingham model with sufficient precision. However, the cement grout shows a nonlinear behavior, which was modeled by the Herschel-Bulkley model. Results indicate that the use of LF has a significant effect on the superplasticizer (Sp) demand of concrete and mortar, for a given slump on one hand. On the other hand, an increase in yield stress, apparent viscosity and flow time of cement grout was obtained when LF is incorporated, which results in a loss of fluidity of the suspensions of LF.