An analytical model of apparent viscosity in bleeding process

• Analytical model was presented for describing apparent viscosity in bleeding process. • The model is based on self-weight consolidation bleeding theory. • The model can predict apparent viscosity variation well. • Increase in apparent viscosity in bleeding process can be modelled. The bleeding of cement slurry influences its key rheological parameters, such as the apparent viscosity. In this paper, we proposed an analytical model for describing the development of apparent viscosity during the bleeding process. In this model, the self-weight consolidation theory was employed to interpret cement slurry bleeding, and the water-cement ratio as an intermediate variable to establish the relationship between the bleeding time and the apparent viscosity. The model requires five parameters, all of which can be determined conveniently through laboratory tests. A series of experiments were employed to validate the proposed model. The results show that this model can predict the apparent viscosity variation during the entire bleeding time, and two increase stages of apparent viscosity during the bleeding process were captured. The limitation of this model and further research are discussed briefly.