Rheological properties of nanomodified cement pastes

Abstract

The study considers the influence of additive based on complex carbon nanotubes and polycarboxylate plasticizer on rheological properties of cement pastes. The rheological studies were conducted using RHEOTESTRN 4.1 rheometer with coaxial cylinders 5, 30, 60, 90 and 120 minutes after the start of mixing, the amount of additive being varied from 0 to 0,8% from the mass of binder. The experiment determined the dependence of shear stress and shear rate. The results were processed using Bingham model. The changes of viscosity and yield stress were plotted against the amount of additives and time. Applying the complex modifier provided the increased plasticizing effect and its integrity in time, which provides the possibility of its application in producing new high-quality concrete.