Rheological characterisations of sulfate-resisting Portland cement concrete with different degrees of workability

The rheological behaviour of concrete having different degrees of workability made with sulfate-resisting Portland cement (SRPC) was evaluated and compared with concrete made using ordinary Portland cement (OPC). The rheological behaviour was monitored by measuring the relative yield stress and relative plastic viscosity at 15 min intervals over a period of 60 min. The concrete prepared with SRPC exhibited similar trends in the variations of relative yield stress and relative plastic viscosity with increasing workability levels as the concrete prepared with OPC. However, at all levels of workability, the concretes prepared with SRPC rather than OPC showed less relative yield stress at all elapsed times. A similar trend was noted in the relative plastic viscosity analysis, except for the very low workability or stiff concrete. Additionally, a correlation between rheological properties and conventional fresh properties (slump and vee-bee time) was developed. The compressive strengths of all samples were determined and analytical characterisations were conducted using zeta potential, X-ray diffraction and field emission scanning electron microscopy analyses. This article may serve as a reference for preparing concrete with various levels of workability based on rheological studies.