Prediction of the Rheological Properties of Fresh Cementitious Suspensions Considering Microstructural Parameters

Abstract

Supplementary cementitious materials (SCMs) are commonly used to partially replace cements. Although it is necessary to investigate the rheological properties of the individual supplementary cementitious materials (SCMs) for understanding complex rheological behaviors of the blended mixes, the study on the investigation of rheological properties of various SCMs such as fly ash, blast-furnace slag, and silica fume, according to various solid volume fractions and prediction models is fairly limited. This study investigated the rheological properties of non-blended cementitious suspensions with Portland cement (PC), fly ash (FA), blast-furnace slag (BS), and silica fume (SF) materials in the experiments and predicted using YODEL (Yield stress mODEL) and Krieger–Dougherty’s (K–D’s) equation. Experiments were designed with various solid volume fractions (ϕ) from 0.28 to 0.44, and the rheological properties of all cementitious suspensions were noted to increase with increasing ϕ, showing an improved flowability at low ϕ. YODEL, derived from the first principles considering particle-size distributions, interparticle forces and microstructural parameters predicted the yield stress. The YODEL predictions were consistent with the experiments with a positive correlation coefficient of above 0.96. K–D’s equation with the maximum particle fractions and intrinsic viscosity as key parameters predicted the plastic viscosity. The K–D’s equation predictions match up with the experiments with a positive correlation coefficient of above 0.94. Both models showed more quantitative predictions without any fitting parameters and could be applied to any multimodal powder suspensions.

Keywords

• rheology
• yield stress
• plastic viscosity
• YODEL
• Krieger-Dougherty’s equation