Investigation into Yield Behavior of Fresh Cement Paste: Model and Experiment

In the present study, a yield stress model of cement paste is developed based on a theoretical approach. In this model, cement particles are assumed as rigid spheres uniformly distributed and suspended in water. The interparticle force is considered resulting from the electrostatic and dispersion forces of the cement particles. Two types of tests - a direct shear and a rheometer test - are performed on a group of cement pastes made with different water-cement ratios (w/c), and the results are used for verification of the validity of the newly developed model. The study demonstrates that the newly developed model can not only predict the yield behavior of cement pastes but also describe the correlations among the yield stresses obtained from different experimental methods.